We camp off the grid most of the time we use our trailer.
I don't waste power by turning on all the lights but I don't skimp either. If it is hot, I run the fan. If it is cold I run the furnace. The pump is on all the time (its not using electricity unless it is pumping. The fridge is on all the time. I have a small solar panel and regulator. If I don't run the furnace, the solar will keep the batteries fully charged on sunny days.
On cloudy days or when it is cold and the furnace runs. I run my generator for two hours in the evening.
If I don't have close neighbors, I run the generator in the morning for an hour to make coffee. I like multiple cups.
We have upgraded to group 27 batteries which do fit in the stock battery box barely. We have added a propane catalytic heater which we don't run when we are sleeping but use to keep the trailer comfortable when we are in it.
You will find that if you boondock a lot, solar and generator are necessary. You will also find that upgrades like led lighting and a catalytic heater make things more comfortable. In fact we are just as comfortable off the grid as on it and we are camping in much more scenic places.