Are all Shopping Cart programs the same?
Yes and no.
Yes, because they all ultimately perform the same basic function of displaying goods, products or services and then handling the complexities of ordering and payment.
No, because different programs will have different capabilities and functionality.
At the lower end of the scale, most Shopping Carts provide product display, ordering and payment facilities, but nothing else. At the higher end of the scale, there are Shopping Carts which provide a completely integrated service covering all aspects of financial and database management, and can handle such complexities as invoicing, credit control, customer & supplier database control and update, stock control, etc. Solutions at the higher end of the market can cost from #5,000 to over #100,000 for the program alone, eg, excluding the cost of integrating the program into the business and building the Catalogue and Website, whilst programs at the lower end can cost from #150 upwards.
Note that an expensive program will not necessarily handle the basic ordering and payment transactions better than a cheaper alternative. It will just have additional functionality and benefits and may require additional, expensive programming to integrate it with your existing systems. Build time is also likely to be longer and cost more as a consequence. Cheaper systems on the other hand can normally be setup and built in a relatively short period of time, and usually provide a very effective, slick ordering facility.
For most small to medium sized businesses, having a cost-effective,online ecommerce shopping facility is probably the most important factor, followed by the cost of keeping the product information up to date. In this respect, a dynamic shopping cart provides the site owner with the maximum control over product updates and prices.