I'll second or third the advice on logs. Plan to sit down with them, get a cup of coffee or tea and calmly and thoroughly look through them from the first page. If the plane is thirty yr. old, you won't spend too much time on the earlier stuff. Even if you are not an A&P, you can understand much of the entries. Watch for some item that's been repaired a number of times, for example. Like someone said, watch for long periods of inactivity [I once looked at a plane that had 0.1 hr. on it between the previous two annuals....] You might speak with a mechanic you know, at home or wherever you normally fly, and get him or her to agree to speak with you over the phone if you find any questions in the logs. Offer to pay them for the time on the phone; they may not charge [they'll be getting your business soon enough], but even if they do, it won't be much. I did this once, and the mechanic didn't like what I read to him, told me how much it might cost to fix it, and we negotiated the purchase price down appropriately.... If you have a friend who owns already, it will be worth gold if they'd go along with you and cast a critical glance at the plane, too. I've done that for a friend, once. Even found a couple things I didn't like....