diff --git a/src/AbstractApi.php b/src/AbstractApi.php
index 83d1c21..0fb7465 100644
--- a/src/AbstractApi.php
+++ b/src/AbstractApi.php
@@ -58,6 +58,7 @@ public function __construct(array $options = array())
      * Set our Client instance
      *
      * @param Client $httpHandler
+     * @return $this
      */
     public function setHttpHandler(Client $httpHandler)
     {
@@ -82,6 +83,7 @@ public function getHttpHandler()
      * Set our LoggerInterface
      *
      * @param LoggerInterface $logger
+     * @return $this
      */
     public function setLogger(LoggerInterface $logger)
     {
@@ -104,6 +106,7 @@ public function getMyshopifyDomain()
      * a new client, with new details
      *
      * @param string $domain
+     * @return $this
      */
     public function setMyshopifyDomain($domain)
     {
diff --git a/src/Api.php b/src/Api.php
index 3d7165a..29e03c7 100644
--- a/src/Api.php
+++ b/src/Api.php
@@ -72,6 +72,7 @@ public function getApiSecret()
      * new client instance
      *
      * @param string $accessToken
+     * @return $this
      */
     public function setAccessToken($accessToken)
     {
@@ -94,6 +95,7 @@ public function getAccessToken()
      * Set our persistent storage interface
      *
      * @param PersistentStorageInterface $storage
+     * @return $this
      */
     public function setStorageInterface(PersistentStorageInterface $storage)
     {
diff --git a/src/Service/AbandonedCheckoutsService.php b/src/Service/AbandonedCheckoutsService.php
index e010a57..1d41815 100644
--- a/src/Service/AbandonedCheckoutsService.php
+++ b/src/Service/AbandonedCheckoutsService.php
@@ -7,7 +7,7 @@
 class AbandonedCheckoutsService extends AbstractService
 {
     /**
-     * List all abandonded checkouts
+     * List all abandoned checkouts
      *
      * @link   https://help.shopify.com/api/reference/abandoned_checkouts#index
      * @param  array $params
diff --git a/src/Service/AbstractService.php b/src/Service/AbstractService.php
index 3db841c..8061e9e 100644
--- a/src/Service/AbstractService.php
+++ b/src/Service/AbstractService.php
@@ -2,59 +2,93 @@
 
 namespace Shopify\Service;
 
+use GuzzleHttp\Client;
 use GuzzleHttp\Psr7\Request;
 use GuzzleHttp\Psr7\Response;
 use Shopify\ApiInterface;
-use Shopify\Object\AbstractObject;
-use Shopify\Inflector;
 
 abstract class AbstractService
 {
-    private $api;
-    private $mapper;
+    /**
+     * Instantiated Guzzle Client for requests
+     * @var Client
+     */
+    private $client;
+
+    /**
+     * The last API response from Shopify
+     * @var Response|null
+     */
+    private $lastResponse;
 
     const REQUEST_METHOD_GET = 'GET';
     const REQUEST_METHOD_POST = 'POST';
     const REQUEST_METHOD_PUT = 'PUT';
     const REQUEST_METHOD_DELETE = 'DELETE';
 
-    public static function factory(ApiInterface $api)
+    public static function factory(ApiInterface $api): AbstractService
     {
         return new static($api);
     }
 
     public function __construct(ApiInterface $api)
     {
-        $this->api = $api;
+        $this->client = $api->getHttpHandler();
     }
 
-    public function getApi()
+    /**
+     * Get the client instance
+     *
+     * @return Client
+     */
+    public function getClient()
     {
-        return $this->api;
+        return $this->client;
     }
 
-    public function request($endpoint, $method = self::REQUEST_METHOD_GET, array $params = array())
+    /**
+     * @param $endpoint
+     * @param string $method
+     * @param array $params
+     * @return mixed
+     */
+    public function request($endpoint, $method = self::REQUEST_METHOD_GET, array $params = [])
     {
-        $request = $this->createRequest($endpoint, $method);
-        return $this->send($request, $params);
+        return $this->send(new Request($method, $endpoint), $params);
     }
 
+    /**
+     * @param $endpoint
+     * @param string $method
+     * @return Request
+     */
     public function createRequest($endpoint, $method = self::REQUEST_METHOD_GET)
     {
         return new Request($method, $endpoint);
     }
 
+    /**
+     * Get the last response from Shopify
+     * @return Response
+     */
+    public function getLastResponse()
+    {
+        return $this->lastResponse;
+    }
+
     public function send(Request $request, array $params = array())
     {
-        $handler = $this->getApi()->getHttpHandler();
         $args = array();
         if ($request->getMethod() === 'GET') {
             $args['query'] = $params;
         } else {
             $args['json'] = $params;
         }
-        $this->lastResponse = $handler->send($request, $args);
-        return json_decode($this->lastResponse->getBody()->getContents(), true);
+        $this->lastResponse = $this->client->send($request, $args);
+        return json_decode(
+            $this->lastResponse->getBody()->getContents(),
+            true
+        );
     }
 
     public function createObject($className, $data)
diff --git a/src/Service/ApplicationChargeService.php b/src/Service/ApplicationChargeService.php
index 541207d..02882e0 100644
--- a/src/Service/ApplicationChargeService.php
+++ b/src/Service/ApplicationChargeService.php
@@ -49,7 +49,7 @@ public function create(ApplicationCharge &$applicationCharge)
         $data = $applicationCharge->exportData();
         $endpoint = '/admin/application_charges.json';
         $response = $this->request(
-            '/admin/application_charges.json', 'POST', array(
+            $endpoint, 'POST', array(
             'application_charge' => $data
             )
         );
diff --git a/src/Service/ArticleService.php b/src/Service/ArticleService.php
index cc3e11a..7abed0a 100644
--- a/src/Service/ArticleService.php
+++ b/src/Service/ArticleService.php
@@ -22,7 +22,7 @@ public function all($blogId, array $params = array())
     }
 
     /**
-     * Receive acount of all Articles
+     * Receive a count of all Articles
      *
      * @link   https://help.shopify.com/api/reference/article#count
      * @param  integer $blogId
@@ -115,7 +115,7 @@ public function delete($blogId, Article &$article)
      * Get a list of all the authors
      *
      * @link   https://help.shopify.com/api/reference/article#authors
-     * @return arrays
+     * @return array
      */
     public function authors()
     {
diff --git a/src/Service/AssetService.php b/src/Service/AssetService.php
index da10a5d..17d62aa 100644
--- a/src/Service/AssetService.php
+++ b/src/Service/AssetService.php
@@ -13,7 +13,7 @@ class AssetService extends AbstractService
      * @link   https://help.shopify.com/api/reference/asset#index
      * @param  integer $themeId
      * @param  array   $params
-     * @return Asset[]
+     * @throws ShopifySdkException
      */
     public function all($themeId, array $params = array())
     {
@@ -26,7 +26,7 @@ public function all($themeId, array $params = array())
      * @link   https://help.shopify.com/api/reference/asset#show
      * @param  integer $themeId
      * @param  array   $params
-     * @return Article
+     * @throws ShopifySdkException
      */
     public function get($themeId, array $params = array())
     {
@@ -39,7 +39,7 @@ public function get($themeId, array $params = array())
      * @link   https://help.shopify.com/api/reference/asset#update
      * @param  integer $themeId
      * @param  Asset   $asset
-     * @return
+     * @throws ShopifySdkException
      */
     public function put($themeId, Asset $asset)
     {
@@ -52,7 +52,7 @@ public function put($themeId, Asset $asset)
      * @link   https://help.shopify.com/api/reference/asset#destroy
      * @param  integer $themeId
      * @param  Asset   $asset
-     * @return void
+     * @throws ShopifySdkException
      */
     public function delete($themeId, Asset $asset)
     {
diff --git a/src/Service/BlogService.php b/src/Service/BlogService.php
index 79949db..ecad0e9 100644
--- a/src/Service/BlogService.php
+++ b/src/Service/BlogService.php
@@ -22,7 +22,7 @@ public function all(array $params = array())
     }
 
     /**
-     * Receivea count of all blogs
+     * Receive a count of all blogs
      *
      * @link   https://help.shopify.com/api/reference/blog#count
      * @return integer
@@ -77,7 +77,7 @@ public function create(Blog &$blog)
      *
      * @link   https://help.shopify.com/api/reference/blog#update
      * @param  Blog $blog
-     * @return void
+     * @throws ShopifySdkException
      */
     public function update(Blog &$blog)
     {
@@ -85,11 +85,11 @@ public function update(Blog &$blog)
     }
 
     /**
-     * Removea blog from Database
+     * Remove a blog from Database
      *
      * @link   https://help.shopify.com/api/reference/blog#destroy
      * @param  Blog $blog
-     * @return void
+     * @throws ShopifySdkException
      */
     public function delete(Blog $blog)
     {
diff --git a/src/Service/CollectService.php b/src/Service/CollectService.php
index f66da79..d328ec6 100644
--- a/src/Service/CollectService.php
+++ b/src/Service/CollectService.php
@@ -30,7 +30,7 @@ public function all(array $params = array())
     public function count(array $params = array())
     {
         $endpoint = '/collects/count.json';
-        $data = $this->request($endpoint);
+        $data = $this->request($endpoint, $params);
         return $data['count'];
     }
 
diff --git a/src/Service/CommentService.php b/src/Service/CommentService.php
index 3a4c17b..0597bc2 100644
--- a/src/Service/CommentService.php
+++ b/src/Service/CommentService.php
@@ -13,7 +13,7 @@ class CommentService extends AbstractService
      * @param  array $params
      * @return Comment[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/comments.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -27,10 +27,10 @@ public function all(array $params = array())
      * @param  array $params
      * @return integer
      */
-    public function count(array $params = array())
+    public function count(array $params = [])
     {
         $endpoint = '/comments/count.json';
-        $response = $this->request($endpoint);
+        $response = $this->request($endpoint, 'GET', $params);
         return $response['count'];
     }
 
@@ -42,10 +42,10 @@ public function count(array $params = array())
      * @param  array   $params
      * @return Comment
      */
-    public function get($commentId, array $params = array())
+    public function get($commentId, array $params = [])
     {
         $endpoint = '/comments/'.$commentId.'.json';
-        $response = $this->request($endpoint);
+        $response = $this->request($endpoint, 'GET', $params);
         return $this->createObject(Comment::class, $response['comment']);
     }
 
@@ -144,7 +144,7 @@ public function remove(Comment &$comment)
     }
 
     /**
-     * Retore a comment
+     * Restore a comment
      *
      * @link   https://help.shopify.com/api/reference/comment#restore
      * @param  Comment $comment
diff --git a/src/Service/CountryService.php b/src/Service/CountryService.php
index 8b56e4d..5e723da 100644
--- a/src/Service/CountryService.php
+++ b/src/Service/CountryService.php
@@ -13,7 +13,7 @@ class CountryService extends AbstractService
      * @param  array $params
      * @return Country[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/countries.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -41,7 +41,7 @@ public function count()
      * @param  array   $fields
      * @return Country
      */
-    public function get($countryId, array $fields = array())
+    public function get($countryId, array $fields = [])
     {
         $params = array();
         if (!empty($fields)) {
@@ -99,6 +99,7 @@ public function update(Country &$country)
      */
     public function delete(Country $country)
     {
-        return $this->request('/countries/'.$country->id.'.json', 'DELETE');
+        $this->request('/countries/'.$country->id.'.json', 'DELETE');
+        return;
     }
 }
diff --git a/src/Service/CustomCollectionService.php b/src/Service/CustomCollectionService.php
index 8117562..62ba832 100644
--- a/src/Service/CustomCollectionService.php
+++ b/src/Service/CustomCollectionService.php
@@ -101,8 +101,7 @@ public function update(CustomCollection &$customCollection)
     public function delete(CustomCollection &$customCollection)
     {
         $endpoint = '/custom_collections/'.$customCollection->getId().'.json';
-        $request = $this->createRequest($endpoint, static::REQUEST_METHOD_DELETE);
-        $response = $this->send($request);
+        $this->request($endpoint, static::REQUEST_METHOD_DELETE);
         return;
     }
 }
diff --git a/src/Service/CustomerService.php b/src/Service/CustomerService.php
index 06270ca..a94d089 100644
--- a/src/Service/CustomerService.php
+++ b/src/Service/CustomerService.php
@@ -110,7 +110,7 @@ public function update(Customer &$customer)
     public function delete(Customer $customer)
     {
         $endpoint = '/customers/'.$customer->id.'.json';
-        $response = $this->request($endpoint, 'DELETE');
+        $this->request($endpoint, 'DELETE');
         return;
     }
 
@@ -134,6 +134,7 @@ public function accountActivationUrl($customerId)
      * @todo   Return CustomInvite, instead of raw object
      * @link   https://help.shopify.com/api/reference/customer#send_invite
      * @param  integer $customerId
+     * @param CustomerInvite $invite
      * @return CustomerInvite
      */
     public function sendInvite($customerId, CustomerInvite $invite = null)
diff --git a/src/Service/DiscountCodeService.php b/src/Service/DiscountCodeService.php
index de42ea0..0a1950a 100644
--- a/src/Service/DiscountCodeService.php
+++ b/src/Service/DiscountCodeService.php
@@ -14,7 +14,7 @@ class DiscountCodeService extends AbstractService
      * @param  array $params
      * @return DiscountCode[]
      */
-    public function all($priceRuleId, array $params = array())
+    public function all($priceRuleId, array $params = [])
     {
         $endpoint = '/price_rules/'.$priceRuleId.'/discount_codes.json';
         $response = $this->request($endpoint, 'GET', $params);
diff --git a/src/Service/EventService.php b/src/Service/EventService.php
index b697aad..898b0ae 100644
--- a/src/Service/EventService.php
+++ b/src/Service/EventService.php
@@ -13,7 +13,7 @@ class EventService extends AbstractService
      * @param  array $params
      * @return Event[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/events.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -27,7 +27,7 @@ public function all(array $params = array())
      * @param  array $params
      * @return integer
      */
-    public function count(array $params = array())
+    public function count(array $params = [])
     {
         $endpoint = '/events/count.json';
         $response = $this->request($endpoint, 'GET', $params);
diff --git a/src/Service/FulfillmentEventService.php b/src/Service/FulfillmentEventService.php
index 3fb3064..79cfade 100644
--- a/src/Service/FulfillmentEventService.php
+++ b/src/Service/FulfillmentEventService.php
@@ -7,7 +7,7 @@
 class FulfillmentEventService extends AbstractService
 {
     /**
-     * Receive a list of all fulfillmen events
+     * Receive a list of all fulfillment events
      *
      * @link   https://help.shopify.com/api/reference/fulfillmentevent#index
      * @param  integer $orderId
@@ -59,7 +59,7 @@ public function create($orderId, $fulfillmentId, FulfillmentEvent &$fulfillmentE
     }
 
     /**
-     * Delete a fufillment events
+     * Delete a fulfillment events
      *
      * @link   https://help.shopify.com/api/reference/fulfillmentevent#destroy
      * @param  integer          $orderId
@@ -70,7 +70,7 @@ public function create($orderId, $fulfillmentId, FulfillmentEvent &$fulfillmentE
     public function delete($orderId, $fulfillmentId, FulfillmentEvent $fulfillmentEvent)
     {
         $endpoint = '/orders/'.$orderId.'/fulfillments/'.$fulfillmentId.'/events/'.$fulfillmentEvent->id.'.json';
-        $response = $this->request($endpoint, 'DELETE');
+        $this->request($endpoint, 'DELETE');
         return;
     }
 }
diff --git a/src/Service/FulfillmentService.php b/src/Service/FulfillmentService.php
index f1b1885..4dd5b91 100644
--- a/src/Service/FulfillmentService.php
+++ b/src/Service/FulfillmentService.php
@@ -6,21 +6,21 @@
 
 class FulfillmentService extends AbstractService
 {
-    public function all($orderId, array $params = array())
+    public function all($orderId, array $params = [])
     {
         $endpoint = '/orders/'.$orderId.'/fulfillments.json';
         $response = $this->request($endpoint, 'GET', $params);
         return $this->createCollection(Fulfillment::class, $response['fulfillments']);
     }
 
-    public function count($orderId, array $params = array())
+    public function count($orderId, array $params = [])
     {
         $endpoint = '/orders/'.$orderId.'/fulfillments/count.json';
         $response = $this->request($endpoint, 'GET', $params);
         return $response['count'];
     }
 
-    public function get($orderId, $fulfillmentId, array $params = array())
+    public function get($orderId, $fulfillmentId, array $params = [])
     {
         $endpoint = '/orders/'.$orderId.'/fulfillments/'.$fulfillmentId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -53,7 +53,6 @@ public function update($orderId, Fulfillment &$fulfillment)
 
     public function complete($orderId, Fulfillment &$fulfillment)
     {
-        $data = $fulfillment->exportData();
         $endpoint = '/orders/'.$orderId.'/fulfillments/'.$fulfillment->getId().'/complete.json';
         $response = $this->request($endpoint, 'POST');
         $fulfillment->setData($response['fulfillment']);
@@ -61,7 +60,6 @@ public function complete($orderId, Fulfillment &$fulfillment)
 
     public function cancel($orderId, Fulfillment &$fulfillment)
     {
-        $data = $fulfillment->exportData();
         $endpoint = '/orders/'.$orderId.'/fulfillments/'.$fulfillment->getId().'/cancel.json';
         $response = $this->request($endpoint, 'POST');
         $fulfillment->setData($response['fulfillment']);
@@ -69,7 +67,6 @@ public function cancel($orderId, Fulfillment &$fulfillment)
 
     public function open($orderId, Fulfillment &$fulfillment)
     {
-        $data = $fulfillment->exportData();
         $endpoint = '/orders/'.$orderId.'/fulfillments/'.$fulfillment->getId().'/open.json';
         $response = $this->request($endpoint, 'POST');
         $fulfillment->setData($response->fulfillment);
diff --git a/src/Service/GiftCardService.php b/src/Service/GiftCardService.php
index 4088e34..6b44bcb 100644
--- a/src/Service/GiftCardService.php
+++ b/src/Service/GiftCardService.php
@@ -13,7 +13,7 @@ class GiftCardService extends AbstractService
      * @param  array $params
      * @return GiftCard[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/gift_cards.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -27,7 +27,7 @@ public function all(array $params = array())
      * @param  array $params
      * @return integer
      */
-    public function count(array $params = array())
+    public function count(array $params = [])
     {
         $endpoint = '/gift_cards/count.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -42,7 +42,7 @@ public function count(array $params = array())
      * @param  array   $params
      * @return GiftCard
      */
-    public function get($giftCardId, array $params = array())
+    public function get($giftCardId, array $params = [])
     {
         $endpoint = '/gift_cards/'.$giftCardId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -96,7 +96,6 @@ public function update(GiftCard &$giftCard)
      */
     public function disable(GiftCard &$giftCard)
     {
-        $data = $giftCard->exportData();
         $endpoint = '/gift_cards/'.$giftCard->id.'/disable.json';
         $response = $this->request($endpoint, 'POST');
         $giftCard->setData($response['gift_card']);
@@ -109,7 +108,7 @@ public function disable(GiftCard &$giftCard)
      * @param  array $params
      * @return GiftCard[]
      */
-    public function search(array $params = array())
+    public function search(array $params = [])
     {
         $endpoint = '/gift_cards/search.json';
         $response = $this->request($endpoint, 'GET', $params);
diff --git a/src/Service/LocationService.php b/src/Service/LocationService.php
index f5b9c65..34dbfff 100644
--- a/src/Service/LocationService.php
+++ b/src/Service/LocationService.php
@@ -13,7 +13,7 @@ class LocationService extends AbstractService
      * @param  array $params
      * @return Location[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/locations.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -28,7 +28,7 @@ public function all(array $params = array())
      * @param  array   $params
      * @return Location
      */
-    public function get($locationId, array $params = array())
+    public function get($locationId, array $params = [])
     {
         $endpoint = '/locations/'.$locationId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
diff --git a/src/Service/MarketingEventService.php b/src/Service/MarketingEventService.php
index 03528bd..66a5cca 100644
--- a/src/Service/MarketingEventService.php
+++ b/src/Service/MarketingEventService.php
@@ -8,13 +8,13 @@
 class MarketingEventService extends AbstractService
 {
     /**
-     * Receieve a list of all Marketing Events
+     * Receive a list of all Marketing Events
      *
      * @link   https://help.shopify.com/api/reference/marketing_event#index
      * @param  array $params
      * @return MarketingEvent[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/marketing_events.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -96,7 +96,7 @@ public function update(MarketingEvent &$marketingEvent)
     public function delete(MarketingEvent &$marketingEvent)
     {
         $endpoint = '/marketing_events/'.$marketingEvent->id.'.json';
-        $response = $this->request($endpoint, 'DELETE');
+        $this->request($endpoint, 'DELETE');
         return;
     }
 
@@ -105,7 +105,7 @@ public function delete(MarketingEvent &$marketingEvent)
      *
      * @link   https://help.shopify.com/api/reference/marketing_event#engagements
      * @param  MarketingEvent $marketingEvent
-     * @return void
+     * @throws ShopifySdkException
      */
     public function createEngagements(MarketingEvent $marketingEvent)
     {
diff --git a/src/Service/OrderService.php b/src/Service/OrderService.php
index 6c518a0..c3fb7e7 100644
--- a/src/Service/OrderService.php
+++ b/src/Service/OrderService.php
@@ -13,7 +13,7 @@ class OrderService extends AbstractService
      * @param  array $params
      * @return Order[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/orders.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -27,7 +27,7 @@ public function all(array $params = array())
      * @param  array $params
      * @return integer
      */
-    public function count(array $params = array())
+    public function count(array $params = [])
     {
         $endpoint = '/orders/count.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -42,7 +42,7 @@ public function count(array $params = array())
      * @param  array   $params
      * @return Order
      */
-    public function get($orderId, array $params = array())
+    public function get($orderId, array $params = [])
     {
         $endpoint = '/orders/'.$orderId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -77,7 +77,6 @@ public function create(Order &$order)
      */
     public function close(Order &$order)
     {
-        $data = $order->exportData();
         $endpoint= '/orders/'.$order->id.'/close.json';
         $response = $this->request($endpoint, 'POST');
         $order->setData($response['order']);
@@ -92,7 +91,6 @@ public function close(Order &$order)
      */
     public function open(Order &$order)
     {
-        $data = $order->exportData();
         $endpoint= '/orders/'.$order->id.'/open.json';
         $response = $this->request($endpoint, 'POST');
         $order->setData($response['order']);
@@ -107,7 +105,6 @@ public function open(Order &$order)
      */
     public function cancel(Order &$order)
     {
-        $data = $order->exportData();
         $endpoint= '/orders/'.$order->id.'/cancel.json';
         $response = $this->request($endpoint, 'POST');
         $order->setData($response['order']);
diff --git a/src/Service/PageService.php b/src/Service/PageService.php
index aa6c7ff..1a93cb6 100644
--- a/src/Service/PageService.php
+++ b/src/Service/PageService.php
@@ -13,7 +13,7 @@ class PageService extends AbstractService
      * @param  array $params
      * @return Page[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/pages.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -27,7 +27,7 @@ public function all(array $params = array())
      * @param  array $params
      * @return integer
      */
-    public function count(array $params = array())
+    public function count(array $params = [])
     {
         $endpoint = '/pages/count.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -42,7 +42,7 @@ public function count(array $params = array())
      * @param  array   $params
      * @return Page
      */
-    public function get($pageId, array $params = array())
+    public function get($pageId, array $params = [])
     {
         $endpoint = '/pages/'.$pageId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -97,7 +97,7 @@ public function update(Page &$page)
     public function delete(Page $page)
     {
         $endpoint = '/pages/'.$page->id.'.json';
-        $response = $this->request($endpoint, 'DELETE');
+        $this->request($endpoint, 'DELETE');
         return;
     }
 }
diff --git a/src/Service/ProductImageService.php b/src/Service/ProductImageService.php
index 8ea9d4c..5c2f9d8 100644
--- a/src/Service/ProductImageService.php
+++ b/src/Service/ProductImageService.php
@@ -14,7 +14,7 @@ class ProductImageService extends AbstractService
      * @param  array   $params
      * @return ProductImage[]
      */
-    public function all($productId, array $params = array())
+    public function all($productId, array $params = [])
     {
         $endpoint=  '/products/'.$productId.'/images.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -29,7 +29,7 @@ public function all($productId, array $params = array())
      * @param  array   $params
      * @return integer
      */
-    public function count($productId, array $params = array())
+    public function count($productId, array $params = [])
     {
         $endpoint = '/products/'.$productId.'/images/count.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -103,6 +103,7 @@ public function update($productId, ProductImage &$productImage)
     public function delete($productId, ProductImage $productImage)
     {
         $endpoint = '/products/'.$productId.'/images/'.$productImage->id.'.json';
-        return $this->request($endpoint, 'DELETE');
+        $this->request($endpoint, 'DELETE');
+        return;
     }
 }
diff --git a/src/Service/ProductService.php b/src/Service/ProductService.php
index 878d0df..ac2371f 100644
--- a/src/Service/ProductService.php
+++ b/src/Service/ProductService.php
@@ -13,7 +13,7 @@ class ProductService extends AbstractService
      * @param  array $params
      * @return Product[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/products.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -27,7 +27,7 @@ public function all(array $params = array())
      * @param  array $params
      * @return integer
      */
-    public function count(array $params = array())
+    public function count(array $params = [])
     {
         $endpoint = '/products/count.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -42,7 +42,7 @@ public function count(array $params = array())
      * @param  array   $fields
      * @return Product
      */
-    public function get($productId, array $fields = array())
+    public function get($productId, array $fields = [])
     {
         $params = array();
         if (!empty($fields)) {
@@ -102,5 +102,6 @@ public function delete(Product &$product)
     {
         $endpoint = '/products/'.$product->id.'.json';
         $this->request($endpoint, 'DELETE');
+        return;
     }
 }
diff --git a/src/Service/ProductVariantService.php b/src/Service/ProductVariantService.php
index 31e610f..1ff9c02 100644
--- a/src/Service/ProductVariantService.php
+++ b/src/Service/ProductVariantService.php
@@ -14,7 +14,7 @@ class ProductVariantService extends AbstractService
      * @param  array   $params
      * @return ProductVariant[]
      */
-    public function all($productId, array $params = array())
+    public function all($productId, array $params = [])
     {
         $endpoint = '/products/'.$productId.'/variants.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -42,9 +42,9 @@ public function count($productId)
      * @param  array   $fields
      * @return ProductVariant
      */
-    public function get($productVariantId, array $fields = array())
+    public function get($productVariantId, array $fields = [])
     {
-        $params = array();
+        $params = [];
         if (!empty($fields)) {
             $params['fields'] = $fields;
         }
@@ -103,6 +103,7 @@ public function update(ProductVariant &$productVariant)
     public function delete($productId, ProductVariant &$productVariant)
     {
         $endpoint = '/products/'.$productId.'/variants/'.$productVariant->id.'.json';
-        $response = $this->request($endpoint, 'DELETE');
+        $this->request($endpoint, 'DELETE');
+        return;
     }
 }
diff --git a/src/Service/ProvinceService.php b/src/Service/ProvinceService.php
index 90333ed..50fd5c4 100644
--- a/src/Service/ProvinceService.php
+++ b/src/Service/ProvinceService.php
@@ -10,6 +10,7 @@ class ProvinceService extends AbstractService
      * Receive a list of all Provinces
      *
      * @link   https://help.shopify.com/api/reference/province#index
+     * @param  integer $countryId
      * @param  array $params
      * @return Province[]
      */
@@ -53,6 +54,7 @@ public function get($countryId, $provinceId)
      * Modify an existing province
      *
      * @link   https://help.shopify.com/api/reference/province#update
+     * @param  integer $countryId
      * @param  Province $province
      * @return void
      */
diff --git a/src/Service/RecurringApplicationChargeService.php b/src/Service/RecurringApplicationChargeService.php
index 1f4cb35..33cc177 100644
--- a/src/Service/RecurringApplicationChargeService.php
+++ b/src/Service/RecurringApplicationChargeService.php
@@ -13,7 +13,7 @@ class RecurringApplicationChargeService extends AbstractService
      * @param  array $params
      * @return RecurringApplicationCharge[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/recurring_application_charges.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -28,7 +28,7 @@ public function all(array $params = array())
      * @param  array   $params
      * @return RecurringApplicationCharge
      */
-    public function get($recurringApplicationChargeId, array $params = array())
+    public function get($recurringApplicationChargeId, array $params = [])
     {
         $endpoint = '/recurring_application_charges/'.$recurringApplicationChargeId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -64,7 +64,8 @@ public function create(RecurringApplicationCharge &$recurringApplicationCharge)
     public function delete(RecurringApplicationCharge $recurringApplicationCharge)
     {
         $endpoint= '/recurring_application_charges/'.$recurringApplicationCharge->id.'.json';
-        $response = $this->request($endpoint, 'DELETE');
+        $this->request($endpoint, 'DELETE');
+        return;
     }
 
     /**
@@ -72,7 +73,7 @@ public function delete(RecurringApplicationCharge $recurringApplicationCharge)
      *
      * @link   https://help.shopify.com/api/reference/recurringapplicationcharge#activate
      * @param  RecurringApplicationCharge $recurringApplicationCharge
-     * @return boolean
+     * @return void
      */
     public function activate(RecurringApplicationCharge $recurringApplicationCharge)
     {
diff --git a/src/Service/RedirectService.php b/src/Service/RedirectService.php
index 5bf8871..30697ef 100644
--- a/src/Service/RedirectService.php
+++ b/src/Service/RedirectService.php
@@ -10,10 +10,10 @@ class RedirectService extends AbstractService
      * Receive a list of all redirects
      *
      * @link   https://help.shopify.com/api/reference/redirect#index
-     * @param  ListOptions $options
+     * @param  array $params
      * @return Redirect[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/redirects.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -27,7 +27,7 @@ public function all(array $params = array())
      * @param  array $params
      * @return integer
      */
-    public function count(array $params = array())
+    public function count(array $params = [])
     {
         $endpoint = '/redirects/count.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -42,7 +42,7 @@ public function count(array $params = array())
      * @param  array   $params
      * @return Redirect
      */
-    public function get($redirectId, array $params = array())
+    public function get($redirectId, array $params = [])
     {
         $endpoint = '/redirects/'.$redirectId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -97,7 +97,7 @@ public function update(Redirect &$redirect)
     public function delete(Redirect $redirect)
     {
         $endpoint = '/redirect/'.$redirect->id.'.json';
-        $response = $this->request($endpoint, 'DELETE');
+        $this->request($endpoint, 'DELETE');
         return;
     }
 }
diff --git a/src/Service/RefundService.php b/src/Service/RefundService.php
index 767fbba..575c0e2 100644
--- a/src/Service/RefundService.php
+++ b/src/Service/RefundService.php
@@ -15,7 +15,7 @@ class RefundService extends AbstractService
      * @param  array   $params
      * @return Refund[]
      */
-    public function all($orderId, array $params = array())
+    public function all($orderId, array $params = [])
     {
         $endpoint = '/orders/'.$orderId.'/refunds.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -31,7 +31,7 @@ public function all($orderId, array $params = array())
      * @param  array   $params
      * @return Refund
      */
-    public function get($orderId, $refundId, array $params = array())
+    public function get($orderId, $refundId, array $params = [])
     {
         $endpoint = '/orders/'.$orderId.'/refunds/'.$refundId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -62,7 +62,7 @@ public function create($orderId, Refund &$refund)
      * Calculate a refund
      *
      * @link   https://help.shopify.com/api/reference/refund#calculate
-     * @return mixed
+     * @throws ShopifySdkException
      */
     public function calculate()
     {
diff --git a/src/Service/ReportService.php b/src/Service/ReportService.php
index c5a8d77..7e0e7d3 100644
--- a/src/Service/ReportService.php
+++ b/src/Service/ReportService.php
@@ -13,7 +13,7 @@ class ReportService extends AbstractService
      * @param  array $params
      * @return Report[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/reports.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -28,7 +28,7 @@ public function all(array $params = array())
      * @param  array   $params
      * @return Report
      */
-    public function get($reportId, array $params = array())
+    public function get($reportId, array $params = [])
     {
         $endpoint = '/reports/'.$reportId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
diff --git a/src/Service/ScriptTagService.php b/src/Service/ScriptTagService.php
index e421413..66ce7db 100644
--- a/src/Service/ScriptTagService.php
+++ b/src/Service/ScriptTagService.php
@@ -13,7 +13,7 @@ class ScriptTagService extends AbstractService
      * @param  array $params
      * @return ScriptTag[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $data = $this->request('/script_tags.json', 'GET', $params);
         return $this->createCollection(ScriptTag::class, $data['script_tags']);
@@ -26,7 +26,7 @@ public function all(array $params = array())
      * @param  array $params
      * @return integer
      */
-    public function count(array $params = array())
+    public function count(array $params = [])
     {
         $data = $this->request('/script_tags/count.json', 'GET', $params);
         return $data['count'];
@@ -40,9 +40,9 @@ public function count(array $params = array())
      * @param  array   $fields
      * @return ScriptTag
      */
-    public function get($scriptTagId, array $fields = array())
+    public function get($scriptTagId, array $fields = [])
     {
-        $params = array();
+        $params = [];
         if (!empty($fields)) {
             $params['fields'] = implode(',', $fields);
         }
diff --git a/src/Service/ShippingZoneService.php b/src/Service/ShippingZoneService.php
index ac4a977..cfe9745 100644
--- a/src/Service/ShippingZoneService.php
+++ b/src/Service/ShippingZoneService.php
@@ -11,7 +11,7 @@ class ShippingZoneService extends AbstractService
      * Return a list of shipping zones
      *
      * @link   https://help.shopify.com/api/reference/shipping_zone#index
-     * @return ShippingZone[]
+     * @throws ShopifySdkException
      */
     public function all()
     {
diff --git a/src/Service/SmartCollectionService.php b/src/Service/SmartCollectionService.php
index 3ab1246..ae08df0 100644
--- a/src/Service/SmartCollectionService.php
+++ b/src/Service/SmartCollectionService.php
@@ -13,7 +13,7 @@ class SmartCollectionService extends AbstractService
      * @param  array $params
      * @return SmartCollection[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/smart_collections.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -41,7 +41,7 @@ public function count()
      * @param  array   $params
      * @return SmartCollection
      */
-    public function get($smartCollectionId, array $params = array())
+    public function get($smartCollectionId, array $params = [])
     {
         $endpoint = '/smart_collections/'.$smartCollectionId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -105,10 +105,10 @@ public function delete(SmartCollection $smartCollection)
      * @link   https://help.shopify.com/api/reference/smartcollection#order
      * @param  integer      $smartCollectionId
      * @param  OrderOptions $options
-     * @return void
+     * @throws ShopifySdkException
      */
     public function order($smartCollectionId, OrderOptions $options)
     {
-
+        throw new ShopifySdkException("SmartCollectionService::order not implemented");
     }
 }
diff --git a/src/Service/ThemeService.php b/src/Service/ThemeService.php
index 1775db6..7fa9c25 100644
--- a/src/Service/ThemeService.php
+++ b/src/Service/ThemeService.php
@@ -14,7 +14,7 @@ class ThemeService extends AbstractService
      * @param  array   $params
      * @return Theme
      */
-    public function get($themeId, array $params = array())
+    public function get($themeId, array $params = [])
     {
         $endpoint = '/themes/'.$themeId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -28,7 +28,7 @@ public function get($themeId, array $params = array())
      * @param  array $params
      * @return Theme[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $endpoint = '/themes.json';
         $response = $this->request($endpoint, 'GET', $params);
diff --git a/src/Service/TransactionService.php b/src/Service/TransactionService.php
index 573b669..cc72668 100644
--- a/src/Service/TransactionService.php
+++ b/src/Service/TransactionService.php
@@ -7,14 +7,14 @@
 class TransactionService extends AbstractService
 {
     /**
-     * Recieve a list of all Transactions
+     * Receive a list of all Transactions
      *
      * @link   https://help.shopify.com/api/reference/transaction#index
      * @param  integer $orderId
      * @param  array   $params
      * @return Transaction[]
      */
-    public function all($orderId, array $params = array())
+    public function all($orderId, array $params = [])
     {
         $endpoint = '/orders/'.$orderId.'/transactions.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -29,7 +29,7 @@ public function all($orderId, array $params = array())
      * @param  array   $params
      * @return integer
      */
-    public function count($orderId, array $params = array())
+    public function count($orderId, array $params = [])
     {
         $endpoint = '/orders/'.$orderId.'/transactions/count.json';
         $response = $this->request($endpoint, 'GET', $params);
@@ -45,7 +45,7 @@ public function count($orderId, array $params = array())
      * @param  array   $params
      * @return Transaction
      */
-    public function get($orderId, $transactionId, array $params = array())
+    public function get($orderId, $transactionId, array $params = [])
     {
         $endpoint = '/orders/'.$orderId.'/transactions/'.$transactionId.'.json';
         $response = $this->request($endpoint, 'GET', $params);
diff --git a/src/Service/WebhookService.php b/src/Service/WebhookService.php
index 131f2e5..4b06b68 100644
--- a/src/Service/WebhookService.php
+++ b/src/Service/WebhookService.php
@@ -13,7 +13,7 @@ class WebhookService extends AbstractService
      * @param  array $params
      * @return Webhook[]
      */
-    public function all(array $params = array())
+    public function all(array $params = [])
     {
         $response = $this->request('/webhooks.json', 'GET', $params);
         return $this->createCollection(Webhook::class, $response['webhooks']);
@@ -26,7 +26,7 @@ public function all(array $params = array())
      * @param  array $params
      * @return integer
      */
-    public function count(array $params = array())
+    public function count(array $params = [])
     {
         $response = $this->request('/webhooks/count.json', $params);
         return $response['count'];
@@ -40,9 +40,9 @@ public function count(array $params = array())
      * @param  array   $fields
      * @return Webhook
      */
-    public function get($webhookId, array $fields = array())
+    public function get($webhookId, array $fields = [])
     {
-        $params = array();
+        $params = [];
         if (!empty($fields)) {
             $params['fields'] = implode(',', $fields);
         }
diff --git a/src/Storage/SessionStorage.php b/src/Storage/SessionStorage.php
index 57c9f3a..c694f21 100644
--- a/src/Storage/SessionStorage.php
+++ b/src/Storage/SessionStorage.php
@@ -8,6 +8,11 @@ class SessionStorage implements PersistentStorageInterface
 {
     protected $prefix = 'SHPFY_';
 
+    /**
+     * @param $key
+     * @return bool
+     * @throws ShopifySdkException
+     */
     public function get($key)
     {
         $this->assertSession();
@@ -17,12 +22,20 @@ public function get($key)
         return false;
     }
 
+    /**
+     * @param $key
+     * @param $value
+     * @throws ShopifySdkException
+     */
     public function set($key, $value)
     {
         $this->assertSession();
         $_SESSION[$this->prefix . $key] = $value;
     }
 
+    /**
+     * @throws ShopifySdkException
+     */
     public function assertSession()
     {
         if (session_status() !== PHP_SESSION_ACTIVE) {