For my money I would pass on it. Way too much money for a VFR only plane that's not been flown much.
You also have to consider the thing never made TBO the first time around and you don't know the quality of the overhaul at this point.
You didn't say if it was hangared or not, but in any case I'd want the wing tanks pulled and have a good look underneath for corrosion and also a good borescope of the engine for added security.
Then I'd talk him down about $10,000 if I could. I just don't think a VFR C150 is worth that much no matter what you do to it. In other words, I wouldn't want to give more than $19K for it, and then that amount if it was in great shape.
