My old apartment had incredibly unprofessional repair staff. I'd call them because my AC would be out, and they'd come over while I was at work (rather than at the agreed-upon time while I was home) and they'd use my bathroom, poke around through my stuff, type on my keyboard, f**k around with my pets, etc.
Needless to say, I was pretty livid.
I setup a camera and caught them, then took the footage to the front office. I got a personal call from the owner of the apartment complex to apologize, and almost the entire repair staff got fired.