Explain that the job WILL entail multiple trips, and WILL incur multiple trip charges, both coming and going, in addition to the installation cost.

Also explain that the system will not be operational until the final day, and maybe other things that are tied to the system will also not be operational (this is fun when it involves HVAC, lighting, and security control).


I actually had a doctor ask me to leave one evening, after he had stressed that the job be finished that day. He was a total AZZ, so my return was two weeks later.