thanks

Without gutting the trailer and replacing the windows, or, as GDE says, ledgering in additional space in walls and ceiling, it's nigh impossible to make a TT into an efficient space to heat. I did my best by gutting out and filling every cavity with as much extruded foam as possible, used thermal breaks on all the framing, changed the furnace to a more efficient heater, have plumbing runs all inside the structure, but.....it is still going to be costly to heat through a Winter if electrical heaters can't be used on an "inluded with rent" situation.

FWIW, a few years back I was contemplating a move to Western ND to work in the oil patch. After estimating costs, I found out it was cheaper to rent a space in a heated RV garage, about $1000/mo. In most areas of the US, an apartment could be had for less.