I can't comment on an auction featured forum but I'm sure with some CSS and creative imagination, you can make it possible with the article thread type that XF 2.1+ offers. I provided a link to my forum as an example, I'm currently using all the built-in features to create a "market" or my vision of a market at the very least. As I've said before, you'll only really need a feedback system to help with that side of things but there is an add-on available for that. I did think about building my own using XF's built-in profile posts but decided against it as it will require work and I wanted to work at the very minimal.
I don't know what other information you need unless you're going to ask me to do it for you but I'm not looking for that kind of work.