Best Web Site to Search for Class A

And don't forget Craigslist to search for local area coaches. As with any online search feature, do not rely on written descriptions. A thorough personal inspection is the only way to insure that the coach will meet your expectations.
Obviously you will want to make sure that all paperwork is in order before any money is exchanged and personally I would not leave any security deposit. Just pay for the coach in full when you pick it up, along with the title, or let your lending institution handle the money transfer.