I bought a C-150H for $14,250 (an impulse buy from a local person), flew it for two years until the engine crapped out, and have since sunk $35K into it (brand new engine, prop, etc., etc.)
I'm fairly happy with it. I maybe could have gotten by with an overhaul vs. a brand new engine, but all in all I like the plane. If I had to go it over again, maybe I would have prefered a much lower time, cleaner "turn key" airplane that had been hangared all its life, etc., but I probably would have had to pay much more up front -- $25K or more. You generally get what you pay for. Are you a mechanic, or do you have a mechanic in mind that will do repairs for you? That makes a big difference.
Do you want to restore the plane to like-new condition - - as I would like to do some year? If so, I'm sure you are intelligent enough to know that that would cost tens of thousands of dollars -- and you probably could never expect to get that money back in resale.
Maybe do as Bill suggests -- get the plane annualled before you buy it, or at least get an estimate for how much an annual inspection would cost.
