My opinion? -- everyone here keeps referring people to eBay or other sales sites. This is a realistic option, because eBay seems to be driving market prices anyway! So if everyone decides on not having a "for sale" section, it's not like vendors are without options.
But I think you DO have an opportunity to make some money while retaining the integrity of the forum, so here's my suggestion:
1 -- Charge a fairly prohibitive fee for people who just want to sell their goods. Say, $15 per item. This will prevent sellers from just flooding the board with dozens of items, or even the same item dozens of times. Make this section of the board so that posts aren't automatic, but must "await moderator approval". That way you can verify payment and suitability of the item for sale (no need to pass a 2001 Nissan Altima, for example), before allowing it through.
2 -- Indicate that sales need to be conducted off the board, the board does not warrant/guarantee/blah-blah-blah, etc.
3 -- Use the terms of service to indicate that "for sale" posts will be monitored by regular board members, who may publicly comment on condition, price, authenticity, etc.
4 -- Offer a lower price for regular board members, say $1 or $2. Now this is where it gets tricky. What's a regular board member? If you set it by number of posts, you're going to have some people who post just to get the discount, and we'll see a hundred miles of posts from "XYZ Vendor" saying "I agree, that's Victorian" and "I agree, that's the right price." Perhaps a voting system? -- if someone applies to be a Preferred Vendor (let's call it), the board can comment on the person's suitability. This will hopefully ensure that only people who have proven their commitment and know-how become Preferred Vendors. (Or, instead of public comment/vote system, perhaps a small board of four or five regular members, who volunteer to do it?)
5 -- Offer free selling to a small number of regular posters who volunteer to moderate the boards. Then you get free help, as well!
just some ideas.
