What is tipping, and why would you need it installed?
But seriously, folks...
Doing an installation on a hot summer day, part of it needed to be done in the attic. Customer was OK with putting it off, but I figured it wouldn't take long. Glad I didn't have a thermometer; I probably would have fainted. He tipped me $50 - I was very appreciative.
Fast forward a couple of years, had two yards of concrete delivered. It was an inaccessible area, so I built a 12' trough the truck could reach. First time I'd done that, and didn't know concrete doesn't flow over wood. The driver helped me hoe-and-shovel it down the trough, screeed off the slab and do a rough float. Only an extra half hour, but hugely valuable to me. He actually apologized for having to charge me extra for exceeding the max unload time, said he'd get in trouble with the company if he didn't. I tipped him $50, and I was very appreciative.