I never lend gear. I learned that lesson 40 years ago.Lent my fins to a buddy's friend. Fins came back ripped, they were shoe fins. My friend said his friend said the fins were ripped before I lent them to him. ok, never again.
One time I borrowed a full set of gear for a non diving good friend of mine. I took my best friend on a beautiful reef, 10' deep. My friend was not certified so I watched him like a hawk. I am not an instructor. The reg. stopped breathing so we surfaced and swam in, no problem except for an angry best friend. When I told the guy I borrowed the gear from, he said, oh yeah," that stuff was in a fire".
Another time I lent me roommate and good friend my wood skis. They came back broken . My roomate said he spoke to someone who said the skis were no good anyway.
People ask me to borrow anything I say no. My neighbor asked to borrow my chain saw. I said no but offered cut down the tree with him. He said no, he was offended, but at least we are still friends.