Hrm...well...I use a content management system for my site called Drupal. It has a module for you to add a 'hosting' product. I assume any type of product could be created though since, either way, you'd have to set up your client's account manually. Most CMS that have ecommerce/shopping cart capability have payment modules. Drupal comes with paypal, authorize.net, and a few other ones. What services you provide on your site have nothing to do with DH.
Most people that I know use paypal as their payment processor instead of getting a merchant account somewhere. You'd have to upgrade to at least a premier account (which is free to do) to be able to take credit card payments.
The Insane Cabbit
My Blog http://www.sounanda.com
My web store:
Send me a pm if you want cms or forum software installed (for a fee)