What are the prop and engine hours, "On Condition" infers they are over TBO ( though in the UK on private cat it can continue to fly on that)
I think the cost of an engine will floor you if and when it is needed
I quote this from a 2007 article
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still drop my jaw when I hear that a new IO-540 from Lycoming is north of $45,000. A freshly overhauled IO-540 will be in the $20-$30K range and may require a core. I don’t have a core.
Lycoming Aircraft Engines - Don George Aircraft Engines and Parts
You have to factor that and the prop into the price..get a licenced engineer to do a survey for you of the aircraft, it is seriously money well spent