On the other hand, it's amazing how an incompetent renter can cause you even more headaches by trying to fix things.     Kitchen drain was leaking (that means, the little kid was playing with the plumbing and pulled it loose, but they'll never say that.)   I went to fix it, "wtf?!"  The tailpiece was almost completely unscrewed.   Things like that don't just happen by themselves.   And, I've *never* seen a case where the leaking joint was the tailpiece.   "Someone try to fix this?"  "Yeah, Justin tried."   "Next time you see him, you want to tell him that I said 'Righty tighty, lefty loosey?'"
Another time, they threatened to call a plumber and deduct the cost from the rent, because I apparently wasn't smart enough to fix a toilet problem.   Three times I had snaked out the toilet and got it flushing.  After they threatened to call the plumber, I finally decided to remove the toilet completely & wash it outside.   (It was disgusting, too.)    Ohhhhh look!   A little kids ball was jammed inside through hole in the bottom of the tank.   How'd that get in there, since the little kid wasn't tall enough to reach in to the bottom & it was too big to fit through without some help.    "Ohhhh, that's where his ball went."   Ohhhhhh look!  An airplane!    Then, the problem: someone had attempted to flush a giant hair clip.   It got wedged in the trap.    A snake and plunger would go past it, and clear out any toilet paper, but as soon as more toilet paper was flushed,  it would build up on the hair clip.     Had they called the plumber, I'd probably  have had to pay $200 for the work.   And, I never would have found out it was the tenant's fault.