I would like to suggest a catagory for sold games. That way the "games for sale" would only show the games that are still available. Once a game is sold, it would then be moved into a Sold folder/catagory. Also if people want to check on what a game sold for, or what the going asking price, it would be easier to find.
I usually make sure games are marked [SOLD] in thread titles and lock them so nobody can bump them months later asking if it is still available.
Mike and I are both site mods, so we have the ability to lock threads. When the thread title is updated with [SOLD] it is locked at the same time. D
I actually don't mind the idea of a SOLD category for archiving purposes. And it does clean up the classifieds. I will do this. That said, when a game has been sold i do ask that the thread owner change the title of their thread to indicate this so we mods know we can move the thread.