easy Ouby, i feel my point was very valid.... A low mileage 1 lady owner car as old as a cinq will probably need alot of servicing after some driving. No use is just as bad as mis-use for a car.
Things to actually check.....?
Rust in the rear arches as James said, very important.
Check that the engine warms up and the fan kicks in and out as it should.. This checks several things at once so is not optional. If the thermostat is stuck open it will not warm up, which is bad for wear and mpg. If the fan doesn't work it will overheat. And generally if the HG has gone and its idling it will overheat even if the fan works.
Other than that is all the normal stuff you would check, general condition of engine bay, condition of oil, levels, check the tyres aren't old and cracked - all the little things that indicate how well a car has been looked after.