Multi-level process since a "ban" in online world is difficult to achieve: 1. Set a cookie (lowest form since cookies get cleaned/deleted, but useful) 2. Reco

Multi-level process since a "ban" in online world is difficult to achieve: 1. Set a cookie (lowest form since cookies get cleaned/deleted, but useful) 2. Recognize username + email address (tied to cookie so multiple usernames/emails can be used) 3. Address - physical shipping address is difficult to constantly change (for a normal person, scammers that use drop addresses are a different story all together) 4. Credit Card number w/associated billing address. The billing address is also difficult to constantly change and would correspond to shipping address. There are additional steps a company can take, if necessary.