Items you have "Discovered that you really use in the Coach.

+1 what wildbill said. IR thermometer to check tires at each stop. Clean hands, and more informative than thumping with the baton.

Earthquake putty and velcro also indispensible, but mostly they are a put in place and forget.

110 voltmeter plugged into an easy to see outlet.

Brian-in-Michigan: me too!!