I look at engine times a different way. If I love the airplane, how many years can I fly it before an overhaul, rather than the linear dollar difference you mention. Additionally, I then add to that....will I have saved enough by then to do it.
My Cardinal was on the borderline. I could sell it for $57,000 (bought it for $53K and flew it two years), but in another 2 or 3 years, I would be overhauling it at a cost of about $20-25K. Now I have a $80K investment in an airplane that would be worth about $70-75K, so I decided to sell it.
The Cherokee, that was just a bone head deal. Just got my annual bill of close to $4K due to repairs needed from years of marginal maintenence. So, I paid $37K, have about $8K more into it after the engine work (and it had a 160 hour engine when I bought it), so I am sitting at $45K. Bad investment....maybe, maybe not. I will still have $35K LESS cash invested into the airplane. It is a low time airframe and now the engine is up to snuff with years of flying in it. Market today is about $42K to $47K so I am probably upside down a few grand, but I know what I have and hopefully it will suit my purposes for many years to come.
Oh...by the way....I have started working on an STC to move the wing on top of the fuselage, but getting some resistence from the FAA about those 7 foot long gear leg extensions. <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />
