Lost Paperwork?

I just looked at an ad in Trade a plane.
It's a Cessna Cardinal, 1968 (fairly cheap)with no paperwork which means to
me, no logs.
Besides the obvious, what kind of hassles is there to lost logs?
If I were to purchase this plane, it would be with the intention of doing a
ground-up resto.after a structural blessing by my A&P.
Say I got it, put in new avionics, new engine, prop overhauled, ADs complied
with, fresh paint and interior. What else am I faced with? Any insurance
hassles?
I really like the Cardinals and see this as a possible opportunity since
Cessna won't make any more of them.

Marty