A real favourite on the bigger jets (BBJ / ACJ) is two way communication with someone on the ground when refuelling. It does not have to be a headset! As long as there is someone outside to "bang on the nose " to attract attention of one in the flight deck, or some pre-arranged comm method, that should suffice.
Also, I recommend accompanying them while they are inspecting. It's much easier to resolve a dumb query there and then, than to have a finding revoked!
Any 'uncontrolled docs' are a gift. So be wary of that old folder with manual excerpts, or loose pages of Perf!
Cheers
Stig