FYI-You can by a special hose from Mr. Heater and have a quick connect in the rig so that you can run off of your propane tank. Much more efficient than house furnace. Mr. Heater is our primary heater.
Our philosophy:
1. Fill up fuel tank before pulling into any CG, we have MH so this feeds our generator, and a full tank means you can leave.
2. Always have full water tank.
3. Always have some emergency food though we travel with plenty of food normally.
4. Fill up propane when at half.
We have learned this throughout the years. Water main breaks(3), full area power loss(gas stations can't pump gas), ran out of propane once(40 years ago, 20 degrees, left lasting impression).