I've mentioned it before, but wouldn't a references section be a good idea for the sales area?
That way, sellers/buyers can check up prospective buyers/sellers, stupid karma 'scores' don't get in the way, and there's more evidence for moderators to look at regarding complaints.
Plus, if someone is blacklisted, people can check up on their sales references to see if they are still a trustworthy seller or not.
Smithy
Makes SDH liable if they recommend a seller who turns out to be a fraudster.
IIf the recommend someone who turns out to be a Scammer, SDH will be blamed for it, and if its not controlled by Mods then it will tun into a bitchfest.