I'm part of a local Facebook community for trading and selling board games. You basically meet in a parking lot during the day and make the trade/purchase, and it's pretty hard to fake the components/packaging of a board game. Possible missing components is the biggest worry, since they're not likely to wait around as you count each component.

Also a lot of these people can be vouched for since someone tends to have dealt with each other at some point.

I've only made a couple of trades through it so far, but it seems to work well.

I think they would do better by allowing groups to convert their group into a marketplace and add marketplace features to groups.

I think they've done that. Certainly I've started seeing a buy/sell tab in some groups.

I should have mentioned it's technically a marketplace group. That being said, considering most people wanting to trade or sell games put up like 10 games at a time and make deals for individual games with individual sellers, the price feature is usually superfluous (sometimes they go $9,999,999 just because).

Given the local aspect of this I think it's more a craigslist killer than an ebay killer. And Craigslist is successful in part because it's not very regulated.

Perhaps feed the AI? I started aggressively flagging scammy ads as such and ads I didn't want to see. Most of what I get now is legit and relevant.

Yeah I don't know why they'd release something like this with no built in moderation.