Yes, the surveyor did the tapping hammer thing and spent a total of 2.5 hours on the boat.
The moisture readings were actually "average" for a 30 year boat according to what he said, but nothing serious.
Thank you guys for all your suggestions so far - I am getting a clearer picture now.
I still like the boat a lot - and will actually enjoy doing some of the repairs myself to learn a few things.
I doubt the owner will make the updates/repairs, as he is in his 80s and his main reason for selling is he's too old/lacks strength, so he'd probably rather just get rid of the boat a.s.a.p