Ecommerce: Custom Shopping Cart vs. Paypal

Cost
One of the main deciding factors between using Paypal and a Custom Shopping Cart is going to be the number of items for sale. With few items, it is more economical to simply use Paypal (they charge a small fee per transaction, and setup is free). A shopping cart will require the purchase of the cart engine ($299-$???) and an SSL certificate ($149) which must be renewed yearly.

Management
The advantage with a shopping cart is that if you have lots of items it can (literally) manage those easier, were-as using Paypal (each item by hand) would be tedious and inefficient. When we create an online store for a client we ask, "do you want to manage your products, pricing, shipping, discounts, inventory, image posting, and most importantly, how many products will you ultimately be selling?" These basics pieces of info are absolutely vital to developing a proper online shopping cart experience.

Look
A shopping cart is typically more advantageous because it's easier to keep a consistent graphic look by designing it to look like the parent website; thus, it looks more professional. However, there is a lot of time spent on the front-end doing the custom styling to match the parent website. When using Paypal, the user clicks a button which will redirect the user to a Paypal purchase window (leaving the parent website) where they will select the amount of the product they want, and proceed with checking out. Yet, a shopping cart is self-contained in that all the information and confirmations are handled within the parent website.

Examples
For a visual, we refer you to the Murfreesboro Symphony Orchestra and Secure Product Sales (MSO uses Paypal, and SPS uses a custom Shopping cart).
SPS: http://www.secureproductsales.com/
MSO: http://www.murfreesborosymphony.com/tickets/

Happy Online Shopping!
—Josh Morrison, Senior Web Designer, Navigation Advertising