The only thing I can add is to check what kind of avionics are in it. It is possible that if it has all new avionics, including a Garmin 430W, that could turn it into a $30k plane.
The main question you should ask is, "What would it cost me to take a common, $15K C-150 and turn it into something of comparable quality?" If that number is more than $30k, then maybe the plane is priced correctly. If it only takes $25 to buy and upgrade another plane to the same condition, then the price is too high.
