For details of the difference between the starter and the max e-commerce project, please give us a call to discuss your requirements.  An e-commerce site tends to be far more bespoke that a basic website and we will be able to ensure that we give you the site that provides exactly what you need.  Here at Firestar Design, we have a number of tools available to build your  e-commerce site, though our preferred cart software is Europe Cart, provided by Kryptronic.  This is very powerful, commercial software, which we can tailer easily to your requirements.  It includes support for mailing lists, shipping calculation and multiple payment gateways.