All your batteries have parasitic loads which all of us have found various ways to work around. Your coach will have a set of switches that remove some, but not all, of them. Safety devices, like your LP leak detector, the radio memory, etc. will still be powered. The small roof mounted solar panel helps a little but don't depend on it.
What most of us do it to try to keep it plugged into AC when it's parked. And add a small charger for the chassis (starting) batteries to keep them topped off. The inverter keeps the house batteries topped but generally not the chassis battery.
If you can't do that, then the best course of action is to remove the ground leads after the batteries are fully charged.