Big Pistons Forever, I agree with you on most points. An aircraft that I consider for purchase would have to have full documentation, an excellent airframe and at least the basic IFR avionics in working condition, but I would allow a high-time engine (say, 200 hours remaining before overhaul) if it's otherwise sound. If I like the way it behaves in the first year of operation, I will get the engine overhauled or zero-timed and install extra avionics and maybe some speed mods.