The following video explains how the shipping cost calculation works in the WordPress Shopping Cart plugin.
Simple Shipping Options
Option 1) Flat Shipping Charge Per Item
If you just want to use flat shipping cost for each item then just put ‘0′ in the ‘Base Shipping Cost’ option and specify the individual shipping cost in the trigger text (shortcode) for each product and you are done. For example, the following shortcode will place a button for a product that charges $2.00 for shipping.
[wp_cart_button name="Test Product" price="10.00" shipping="2.00"]
Option 2) Flat/Fixed Shipping Charge Per Checkout (no matter how many items in the cart)
If you just want to use a fixed shipping cost for the cart no matter how many items are in the cart then you can achieve this by specifying this fixed amount in the base shipping cost. Remember, the base shipping cost is only added to the cart if a product in the cart has individual shipping value specified (this way if a customer buys digital product he doesn’t get charged any shipping). Use an individual shipping value of “0.001″ for your physical items which won’t increase the shipping cost but will trigger the base shipping cost to be added as a fixed shipping rate. For example, use the following shortcode:
[wp_cart_button name="Test Product" price="10.00" shipping="0.001"]
Giving Shipping Discounts
What if you want to be a little more intelligent with the shipping cost calculation and want to use ‘Base Shipping Cost’ in conjunction with the individual product shipping cost to offer your customers a better shipping price? You can do that too.
The base shipping cost is added to the total of the individual products shipping cost. So for example if you had two products that costs $50 each and you want to charge $10 shipping for each item then someone buying both the products whould have to pay $100(product cost) + $20(shipping cost) = $120(total). That is not a very realistic shipping price since you are shipping both the products to the same address in one package so it will probably cost you $15 instead of $20.
How do you handle this situation?
You use a base shipping cost of $5 and indidividual product shipping cost of $5.
Now when someone buys both the products the shipping cost will be calculated as following:
$5(shipping for product1) + $5(shipping for product2) = $10(total individual products shipping cost)
Total shipping cost = $10(total individual products shipping cost) + $5(base shipping cost) = $15!
When someone buys one product the shipping cost will be calculated as following:
$5(shipping for product1) = $5(total individual products shipping cost)
Total shipping cost = $5(total individual products shipping cost) + $5(base shipping cost) = $10! (this is the shipping you wanted to charge for one product)
So, hopefully you can see that using the base shipping cost in conjunction with the individual product shipping cost you can be very dynamic in determining the total shipping cost for a purchase.
Option 3) Use PayPal’s Profile Based Shipping
You can also configure the shipping in your PayPal merchant account profile then tell the shopping cart to use your profile based shipping.
Step 1: Check the “Use PayPal Profile Based Shipping” field in the settings menu of this plugin
Step 2: Configure your PayPal profile based shipping in your PayPal account.
Note: The simple shopping cart can only do amount based profile shipping. The weight based profile shipping is only available in the WP eStore plugin.
Visit the WordPress Shopping Cart Plugin Page.