I've worked hard with AWBS to get VM through their development. Except for one minor reseller bug the package is just about good to go with VMPro. It's a particularly powerful package where they've incorporated enom domain sales. The down side if you want to sell domains to boot is the pricing and overhead you need to maintain.
William,
You need a separate billing system to do that. There are a few that already support Virtualmin Professional. Please refer to this FAQ entry:
http://www.virtualmin.com/faq/one-faq?faq_id=1511#31788
I've worked hard with AWBS to get VM through their development. Except for one minor reseller bug the package is just about good to go with VMPro. It's a particularly powerful package where they've incorporated enom domain sales. The down side if you want to sell domains to boot is the pricing and overhead you need to maintain.
Best to use a standalone domain sales such as http://domainmiddleman.com