As a designer pick a cart system

you would find easy to manipulate...

http://www.in-commerce.net/
(395.00 for just the software OR $59.00 per month hosting which comes
with the $395.00 software installed already)

http://www.cs-cart.com/ (125.00)

http://www.codetosell.com/product_de...&category_id=0
(299.00)

http://www.squirrelcart.com/pricing.php (109.00 single site license)

On all of these look at the demo's and check them out, from the demo's
you will be able to see what we can do design wise color / scale /
style...