I used to be very specific with which 4-5 friends could potentially borrow the tractor ... they have experience and or money if there were issues.
I have adjusted my list down as 2 of them proved to me ... never again, their experience was insufficient. I'm glad that I could help them out, and nothing broke, but just not worth it.
now my list is
1) son in law - he knows more about tractors than I ever will, a farm kid
2) mechanic / farmer friend - he knows more about tractors than I ever will, also grew up on a farm
3) good friend / (heavy) equipment operator, career - he's a genius when it comes to operating equipment
4) good friend / all around mechanic handy-man - (new, since original list)
ALL of them are very capable, trustworthy, and able to do / pay for repairs
That's it. I need the equipment for my own use.