Your Permit aeroplane will have an Engine Log Book and an Aircraft Log Book.
All work done should be cross-referenced to the Worksheets. A new Permit is good, of course. Check the radio, if installed, is legal (although this is not insurmountable - just more paperwork).
Bear in mind that a good inspector will be able to look at things and state his/her opinion, but there will always be things that cannot be known. An inspector's signature on the application for the Annual is merely verfication that on
that day, things were as decribed and in order.
If your inspector can't find anything drastically wrong, or you agree that any work that needs doing is worth doing, buy the teas and start negotiating.
Having bought three aircraft, I've only done it 'right' once. First time there were no surprises, second time was a learning experience but still allowed me several hundred hours of pleasure as well and the third time the 'unknown' element couldn't have been discovered anyway.
There are no guarantees, just lots of faith, a generally good community of people and always lots of advice, which you don't have to take.
Does that help at all? If not, please see previous paragraph.
Edited to add that you will, of course, be taking someone familiar with the type of aeroplane you are viewing: at very least a wood and fabric man for a wood and fabric aeroplane, for example.
