As Media is my field I can tell you that that name should be worth considerably more than quoted so far. A "media buy" is a very common and well known term in the advertising business. Large companies hire agencies to make media buys for them. It is a real science, so I think it is a very attractive name for an agency specializing in media buying to use. I would aim for a minimum of $500 on it and I think it could pull 4 or 5 times that if the right company finds it.