Once you have located a plane that looks promising, find out who the
owner uses for a mechanic (and dont use HIM). Now, get the AOPA guide
or similar (www.airnav.com), that will list FBO's and mechanics at
airfields. Call one at the airfield where the plane is (or nearby
airfield if none where plane is) and tell him you want him to do three
things. Compression test, look for corrosion, and look at the logs.
Tell him you are willing to pay him for three hours work. Have him
call you back after the inspection. Now, YOU can tell pretty much
everything else about the condition of the avionics (use every one on
a test flight), paint, upholstry and tires, brakes etc. That is what I
would recommend.