diff --git a/database/factories/ProductFactory.php b/database/factories/ProductFactory.php
index b3b3b4d..2ac5c14 100644
--- a/database/factories/ProductFactory.php
+++ b/database/factories/ProductFactory.php
@@ -31,18 +31,6 @@ class ProductFactory extends Factory
         ];
     }
 
-    public function onSale(): static
-    {
-        return $this->state(function (array $attributes) {
-            $regularPrice = $attributes['regular_price'];
-            return [
-                'sale_price' => $regularPrice * 0.8,
-                'sale_start' => now()->subDay(),
-                'sale_end' => now()->addWeek(),
-            ];
-        });
-    }
-
     public function outOfStock(): static
     {
         return $this->state([
diff --git a/src/Models/Product.php b/src/Models/Product.php
index 2fa3e2f..8811e6e 100644
--- a/src/Models/Product.php
+++ b/src/Models/Product.php
@@ -191,9 +191,13 @@ class Product extends Model implements Purchasable, Cartable
 
     public function isOnSale(): bool
     {
+        if (!$this->sale_start) {
+            return false;
+        }
+
         $now = now();
 
-        if ($this->sale_start && $now->lt($this->sale_start)) {
+        if ($now->lt($this->sale_start)) {
             return false;
         }
 
@@ -210,8 +214,7 @@ class Product extends Model implements Purchasable, Cartable
             return $this->sale_price;
         }
 
-        $defaultPrice = $this->defaultPrice()->first();
-        return $defaultPrice ? $defaultPrice->price : $this->regular_price;
+        return $this->defaultPrice()->first()?->getCurrentPrice();
     }
 
     public function isInStock(): bool
diff --git a/src/Models/ProductPrice.php b/src/Models/ProductPrice.php
index ac0b539..34cd9f7 100644
--- a/src/Models/ProductPrice.php
+++ b/src/Models/ProductPrice.php
@@ -50,4 +50,13 @@ class ProductPrice extends Model implements Cartable
     {
         return $query->where('active', true);
     }
+
+    public function getCurrentPrice(): float
+    {
+        if ($this->sale_unit_amount && $this->sale_unit_amount < $this->unit_amount) {
+            return $this->sale_unit_amount;
+        }
+
+        return $this->unit_amount;
+    }
 }
diff --git a/src/Traits/HasShoppingCapabilities.php b/src/Traits/HasShoppingCapabilities.php
index 09d4acc..cb5e274 100644
--- a/src/Traits/HasShoppingCapabilities.php
+++ b/src/Traits/HasShoppingCapabilities.php
@@ -205,7 +205,8 @@ trait HasShoppingCapabilities
     public function getCartTotal(?string $cartId = null): float
     {
         return $this->cartItems()->get()->sum(function ($item) {
-            return $item->purchasable->getCurrentPrice() * $item->quantity;
+            dump('getCurrentPrice',get_class($item->purchasable),$item->purchasable->getCurrentPrice());
+            return ($item->purchasable->getCurrentPrice() ?? 0) * $item->quantity;
         });
     }
 
diff --git a/tests/Feature/PurchaseFlowTest.php b/tests/Feature/PurchaseFlowTest.php
index fe7d65d..7b2c8a5 100644
--- a/tests/Feature/PurchaseFlowTest.php
+++ b/tests/Feature/PurchaseFlowTest.php
@@ -138,6 +138,9 @@ class PurchaseFlowTest extends TestCase
         $product1 = Product::factory()->withPrices(unit_amount:40)->create();
         $product2 = Product::factory()->withPrices(unit_amount:60)->create();
 
+        $this->assertNotNull($product1->getCurrentPrice());
+        $this->assertNotNull($product2->getCurrentPrice());
+
         $user->addToCart($product1, quantity: 2);
         $user->addToCart($product2, quantity: 1);
 
diff --git a/tests/Unit/ProductPricingTest.php b/tests/Unit/ProductPricingTest.php
index 9014f20..3385d24 100644
--- a/tests/Unit/ProductPricingTest.php
+++ b/tests/Unit/ProductPricingTest.php
@@ -13,23 +13,25 @@ class ProductPricingTest extends TestCase
     /** @test */
     public function it_returns_regular_price_when_not_on_sale()
     {
-        $product = Product::factory()->create([
-            'regular_price' => 100,
-            'sale_price' => null,
-        ]);
+        $product = Product::factory()->withPrices(2, 100)->create();
 
+        $this->assertEquals(2, $product->prices()->count());
+        $this->assertFalse($product->isOnSale());
+        $this->assertNotNull($product->defaultPrice()->first());
         $this->assertEquals(100, $product->getCurrentPrice());
     }
 
     /** @test */
     public function it_returns_sale_price_when_on_sale()
     {
-        $product = Product::factory()->create([
-            'regular_price' => 100,
-            'sale_price' => 80,
-            'sale_start' => now()->subDay(),
-            'sale_end' => now()->addDay(),
-        ]);
+        $product = Product::factory()
+            ->withPrices(2, 100)
+            ->onSale(
+                sale_price: 80,
+                sale_start: now()->subDay(),
+                sale_end: now()->addDay(),
+            )
+            ->create();
 
         $this->assertEquals(80, $product->getCurrentPrice());
     }