I'm going to guess you're unfamiliar with StubHub? That's not a knock, totally pure question. TM and StubHub are two completely separate ticketing agents, but StubHub is a 3rd Party/resell ticketing agent, but it's one of, if not the only legit one. You can resell your tickets on their website the way Tickemaster normally WOULD allow you to, if they allowed Potter tickets to be resold at all. You can still transfer tickets via Ticketmaster of course, but TM hasn't allowed the actual reselling of Potter tickets at all ( I think?). You can put up your Potter tickets up on StubHub for resell, and when/if someone buys them it'll put those tickets into their StubHub account automatically, you don't have to do anything about that. Finance wise, I'm assuming you'll get the money paid by the StubHub buyer since YOU would be the seller. I've only bought tickets via StubHub, I haven't tried to resell tickets there as of yet, so someone else who knows more about that part can let you know those details :)