This store sells used dress clothes. Some of it looks brand new and other stuff not so much. The prices are reasonable but it is very hard to find average sizes that are decent looking. The best stuff is either for really tall or really short men. Most of the common size suits are ugly or not in style.
They do have lots of tuxedos if you are looking for one of those.
I would recommend they offer tailor services to help accommodate the size issues.
Good luck hunting and temper your expectations.