timestyles: The only 100% accurate way of setting up a website with this idea is either for detailsme to provide auctions on Trademe and for people to bid $1 using buy now, and then detailsme will know the accurate email address, or for people to register with detailsme, then they are presented with a code. They place this code on an auction that they run and detailsme links the two together. Why didn't they think of this?
Good way to implement a checking system to verify a person has control of their own account. My solution was to provide your username/password and the detailsme site would check if it's able to login as you. Insecure, but it would work.
What would TradeMe's recourse be over this site? Surely a list of usernames and contact details it outside their grasp?