Unfortunatly not everyone is a member to this forum before actually selling his account
But i do hate that honest people that don't try to scam get set back by this kind of bullshyit
i do think there are good ways to ensure the account is not someone else's, for example making a level 1 character on the game and actually talking to the character that is being sold.
Also i think a good way to ensure it's real, is to let the seller put it on Ebay for example. This way you got a middle man sort of speak