To the OP-
Here's a strategy that I used when shopping for a Mooney that you could apply to this Mooney or any other. First, put together a realistic list of must haves and features that you would like your Mooney to have in the end. Then, place priorities on these things. After that work out a realistic budget for a completed plane, not necesaarily the cost of the plane you might buy. Do the research here, on the AOPA forums, asking around and in the magazines on how much upgrades cost. Trade a Plane really helps. Once you have in mind things that are important to you, it's pretty easy to make a spreadsheet to qualify or disqualify a candidate plane. Look a planes features in both the plus and minus column and then figure how much it's going to cost you to get it to the completed plane inside your budget. Also remember that there will no doubt be surprises even if you do get a great prebuy, so budget for that too. Even if a plane seems high in an ad, call anyways because most sellers these days are willing to knock a bunch off. This guy probably will too.
Good luck!
Oh, and I think this plane is a bit over priced because the avionics are pretty poor. It does have other good features though, so see if the owner will work with you, but I would not pay $57k for it even if radios are not a priority for you.