I was showing an aircraft to an engineer who was checking it out for a buyer.
he said something which might be relevant to your purchase.
Are you buying an aircraft or someones headache?
The numbers have to work ie is it so cheap that even with the costs involved to bring it up to form you are still quids in then go ahead.
If your instincts tell you that you are buying someones headache / problem then walk away.
Pace