UTW - Good question & one I too haven't really been able to find anyone who you can pin down to get an answer from. Post PPL I too would like to acquire a non-complex single for hour-building, but no-one even seems to be able to offer ball-park figures for likely inspection & maintainance costs.
Ludwig's comparison with Ford car dealers is interesting as pretty much all main dealers within the motor industry operate "menu pricing" for all routine servicing and replacement of common parts. Where this isn't the case there are published criteria for establishing the labour element of all repair work & the cost of spares is not a "trade-secret". There appears to be no similar transparancy of pricing in the aircraft engineering business. This would appear to give the punter every chance of being ripped off.
OK - so aircraft aren't cars, the industry is less competative and there is more regulation, but I cannot see why a transparent pricing structure is too much to ask for. Why not have "menu-pricing" or some other form of "indicative" pricing at least for your plain old c152's and pa28's etc.
OK. Rant over,
Mr. Wolfie