diff --git a/src/Basket.php b/src/Basket.php
index f01a8b1..749a521 100755
--- a/src/Basket.php
+++ b/src/Basket.php
@@ -60,9 +60,7 @@ public function __construct(StorageInterface $store, IdentifierInterface $identi
         $this->id = $this->identifier->get();
 
         // Restore the cart from a saved version
-        if (method_exists($this->store, 'restore')) {
-            $this->store->restore();
-        }
+        $this->store->restore();
 
         // Let our storage class know which cart we're talking about
         $this->store->setIdentifier($this->id);
diff --git a/src/Identifier/Cookie.php b/src/Identifier/Cookie.php
index 8f9aae7..8a0d3b3 100755
--- a/src/Identifier/Cookie.php
+++ b/src/Identifier/Cookie.php
@@ -34,7 +34,7 @@ class Cookie implements IdentifierInterface
      */
     public function get(): string
     {
-        if (isset($_COOKIE['cart_identifier'])) {
+        if (! empty($_COOKIE['cart_identifier'])) {
             return $_COOKIE['cart_identifier'];
         }
 
diff --git a/src/Identifier/Runtime.php b/src/Identifier/Runtime.php
index 443c4e9..6878c7a 100755
--- a/src/Identifier/Runtime.php
+++ b/src/Identifier/Runtime.php
@@ -28,7 +28,7 @@
 class Runtime implements IdentifierInterface
 {
     /** @var string */
-    protected static $identifier;
+    protected static string $identifier = '';
 
     /**
      * Get the current or new unique identifier.
@@ -37,7 +37,7 @@ class Runtime implements IdentifierInterface
      */
     public function get(): string
     {
-        if (isset(static::$identifier)) {
+        if (! empty(static::$identifier)) {
             return static::$identifier;
         }
 
diff --git a/src/Item.php b/src/Item.php
index 5bfa578..1e3ea69 100755
--- a/src/Item.php
+++ b/src/Item.php
@@ -101,7 +101,7 @@ public function tax(): float
         $price = $this->totalPrice();
         $quantity = $this->quantity;
 
-        return (float) $this->tax->rate($price * $quantity);
+        return $this->tax->rate($price * $quantity);
     }
 
     /**
@@ -121,7 +121,7 @@ private function totalPrice(): float
             }
         }
 
-        return (float) $price;
+        return $price;
     }
 
     /**
@@ -139,7 +139,7 @@ public function total($includeTax = true): float
             $price = $this->tax->add($price);
         }
 
-        return (float) ($price * $this->quantity);
+        return ($price * $this->quantity);
     }
 
     /**
@@ -177,7 +177,7 @@ public function single($includeTax = true): float
             $price = $this->tax->add($price);
         }
 
-        return (float) $price;
+        return $price;
     }
 
     /**
diff --git a/src/Storage/Runtime.php b/src/Storage/Runtime.php
index 40a8593..0c9bee8 100755
--- a/src/Storage/Runtime.php
+++ b/src/Storage/Runtime.php
@@ -30,7 +30,7 @@
 class Runtime implements StorageInterface
 {
     /** @var string */
-    protected string $identifier;
+    protected string $identifier = '';
 
     /** @var array */
     protected static array $cart = [];
diff --git a/src/Tax.php b/src/Tax.php
index 7ef5408..5e30494 100755
--- a/src/Tax.php
+++ b/src/Tax.php
@@ -41,18 +41,18 @@ class Tax
      * automatically.
      *
      * @param float $value The percentage of your tax (or price before tax)
-     * @param null $after The value after tax
+     * @param null|mixed $after The value after tax
      */
     public function __construct(float $value, $after = null)
     {
         $this->percentage = $value;
 
         if ($after != null && is_numeric($after)) {
-            $this->percentage = (($after - $value) / $value) * 100;
+            $this->percentage = (float) ((($after - $value) / $value) * 100);
         }
 
-        $this->deductModifier = 1 - ($this->percentage / 100);
-        $this->addModifier = 1 + ($this->percentage / 100);
+        $this->deductModifier = (1 - ($this->percentage / 100));
+        $this->addModifier = (1 + ($this->percentage / 100));
     }
 
     /**
@@ -64,7 +64,7 @@ public function __construct(float $value, $after = null)
      */
     public function deduct(float $price): float
     {
-        return (float) ($price * $this->deductModifier);
+        return ($price * $this->deductModifier);
     }
 
     /**
@@ -76,7 +76,7 @@ public function deduct(float $price): float
      */
     public function add(float $price): float
     {
-        return (float) ($price * $this->addModifier);
+        return ($price * $this->addModifier);
     }
 
     /**
@@ -88,6 +88,6 @@ public function add(float $price): float
      */
     public function rate(float $price): float
     {
-        return (float) ($price - $this->deduct($price));
+        return ($price - $this->deduct($price));
     }
 }