eCommerce

Attempting to setup a web site for a retail vendor. Is it possible to use a web hosting company with VeriSign Payflow for the shopping cart? If so, how will I track all transactions of inventory for the vendor? I’m told that CGI scripts at the webhosting site can be used for the shopping cart, but I’m still unsure about the inventory side. Maybe a SQL server and IIS Server together and just forget about the web hosting site? Just confused….HELP!!