Everything Gary said, but one more thought ... are you buying to keep for a lifetime, or do you think you might sell in a few years? If you might sell it relatively soon, the missing logs might become your issue. If you have lots of the information Gary suggested, and you want to keep the airplane for lots of years (I use "lots" intentionally, to suggest that what one considers long term someone else might think short term) then the missing logs isn't as important. Most buyers will consider missing logs as a liability and will want a discounted price on that basis.
