Eligibility rules define who can purchase. Some platforms require account age, verification status, or subscription tier before accessing premium usernames. This prevents speculation and ensures buyers are legitimate users.
Pricing tiers provide transparency. Single characters: $X. Two characters: $Y. Dictionary words: $Z. Published pricing prevents negotiation overhead and sets expectations. Dynamic pricing based on demand is possible but adds complexity.
Transfer policies handle existing claims. If someone already registered a username you want to monetize, what happens? Forced transfers create legal risk. Buyback offers are safer. Grandfathering existing users is the most conservative approach.
Refund and dispute policies protect both parties. What if someone buys a username that turns out to be trademarked? What if they want to sell it back? Define these scenarios in advance.