We have it in the Concorde, the garage and all underfloor lockers including the tanks are in heated compartments, yes we can turn off the garage and bedroom area, we can also have free engine heat and hot water circulated around the van whilst driving,
Ours is the 8 kw version we live full time and keep around 17.5 deg
Cooking fridge heating is £3 per day in winter and 75 p in summer,