I had two clients who remained with me throughout their junior, college and pro(1) careers. The older player was a VERY highly ranked junior, traveling the world with 12-15 strung frames each trip. On the occasion that her parent(s) would join her in Europe or other parts of the world, they would take replacement frames and bring back the others for service.
I often wondered what would happen if I were to 'disappear'. Didn't happen until they 'retired'; but one story from the Italian Junior ?Open? was revealing. The young lady needed one frame strung, just in case. At the tournament venue, she was charged the equiv. of $50 US for LABOR(with her supplied syn) in a mid-sized Prince Graphite(as in UNDER 15 minutes)! She hit about 6 balls with it and put it back in her bag. Upon her return, I could spot that racket from across the room. I'm pretty sure my Scottie could have done better and she doesn't have thumbs!!! (AND this was around the turn of the century, when FIFTY BUCKS was worth something!)
Good thing she wasn't playing in the OP tournament! SOMEbody would have some 'splainin' to do!!!