I've been doing a lot of selling/buying in the past couple of months and all of my deals with other SIGForum members has been fantastic, but I don't know if bumping the thread after a sale is what I should do to state that everything was good. Additionally that would make searching for feedback on a specific member very convoluted when trying to look back through random sales posts. Additionally, I see that a lot of people delete their threads or clear them out after a sale though. Has there ever been discussion for a feedback subforum?

I searched but couldn't find any information

The issue here is that the classifieds section is already our most intensive work-generating room.

If we did establish a feedback room, how would we police it in terms of making sure feedback left for a particular seller was accurate?

We could make an only-positive feedback rule, but then there is the possibility of people shilling themselves with smurf accounts.

Our current rule is caveat emptor, and without adding a lot more work for ourselves, that's probably were it's going to stay.

If you need to provide references for a deal, the best I can suggest is to keep a list of established members who've had good deals with you and are willing to be references for you.

If the buyer wants to contact you for references, that's a start.

As far as people deleting their own threads, that's not encouraged. Some people do it to provide privacy for themselves or their buyers I guess. But it's never been a requirement and I don't personally encourage it, because threads that are still up provide some market data for someone who might be interested in purchasing or selling a similar item.