My Engineer is so Paranoid about log books that he will not allow them to travel in the Aircraft and I have to deliver and collect them in Person, 2 hours drive away. He says without log books the aircraft is worth little in financial or insurance terms.
His son also an engineer who carries out most of the work also collects and flies the aircraft back for me after maintenance which adds to the feel good factor and gives him a chance to see how it flies.
It also saves the hassle of Ferry flights ( they leave their aircraft with me which means it encourages them to complete the work quickly ) I just pay the fuel and a big boys breakfast at collection and return in the airport cafe.
I like engineers who fly aircraft they have worked on but they seem to be a rare breed these days! By the way I fly a LAA Permit aircraft so nothing flash or complicated!
I complete the flight entries in the aircraft log books and my engineer ( the father ) writes up the necessary endorsements.