I have three flat tops, and don't lend them to perfect strangers, but make a decision whether or not to loan them on a person by person basis. I loaned my favourite guitar to a young lady on Saturday for a show we were doing. She didn't have her guitar, but I had seen her play before and knew that she was not a basher. I have a good friend who has a junky guitar and has asked me to use my guitar. Seeing the scratches on his guitar and knowing how he bashes it, I said,"No."
I have put some scratches and dings on all of my instruments, but I don't want anyone else doing it.