There is plenty I don't know, but I have had some direct experience on these coaches. I lived in mine full time for several years just before retiring, since I was working in a state some distance from my real residence.
The heated basement does depend on the running of the coach furnace system, so it needs propane and electricity to get the heat to circulate in the basement compartments. If your coach is unoccupied over the winter, you might want to winterize or take some additional actions. In my case I did not want to keep moving the coach for filling my on-board tank so the park I was renting in allowed the rental of an external propane tank that they took and filled periodically. Even with that, I used small ceramic electric heaters to heat the basement (and oil filled electric heaters in the living space...) just to avoid the noise of the furnace fans.
One thing to be aware of is that the basement heat of any type is not going to be evenly distributed -- particularly if your basement is rather full. I found that the water manifold was in an area that was not getting much heat, so I placed a 'goldenrod' heat stick in that bay to ensure that no water branches got frozen and the pump would work properly if there was a brief power failure or we lost park water service.
Another trick is to turn off the water to the ice maker on the fridge -- that plumbing is in the exterior wall near the access cover and not much heat gets there either.
I have never looked into adding heating pads to teh tanks but know it must not be very easy to do since they are between the floor of the coach and the ceiling of the basement for the most part. And you won't need to do that if you occupy your coach year round (or winterize properly if you don't...)
2007 Tour Master T40C
Acura MDX toad
"It takes a great deal of time to recover from any improvement..."