One thing that I have learned is that it pays to be nice to the onsite people who show you to the generator. I went to one site where the building maid let me through the building. She was fairly young and it was obvious that she doesn't want to be a cleaning lady her whole life. We were talking lots and she explained that she does reiki which is some sort of eastern style healing.... Thing. I don't know how to describe it but she offered me a free session. Everything becomes more appealing when it's free!
Another situation was this one job I had to cancel and reschedule last minute because I was stuck at another site with a broken down unit. The contact lady was a bit annoyed so I told her I would bring her a coffee. Then the rescheduled day came and I grabbed a coffee for her on my way there. When I get to site I call her and she says "well you're going to have to wait a half hour because I'm not at the building right now". I say that is ok and let her know I grabbed her a coffee. Suddenly that half hour turned into five minutes and I didn't have to wait around.
Just yesterday I went to a site where the contact was this resident, Mrs. Frase, who lets all the contractors into the building as a little job to keep her entertained. Well she let me into her apartment to see her ocean front view and use her guest bath. She also told me that her 92nd birthday is coming up in a couple weeks! I was pretty impressed. I hope I'm in that good of shape when I'm 92:)