We've had a bought of cold weather lately with overnight temps in the high teens and daytime temps in the mid thirties, and lately, snow. The good news is that things have held up well and the only thing I wish I had done was to heat tape and insulate the 3/4" hose from the mascerator pump to the sewer cleanout at the house. Normally I leave the gray water valves open and let them drain continuously but with the cold weather it freezes up. Not a big problem since I have a back up hose I temporarily connect to drain the tanks then remove it and make sure it is drained of all fluids, but the gray water tanks need to be emptied every other day and if the freezing weather last more than a few days, which it hasn't so far this winter, then it does become a pain in the butt.
As for heat, with the furnace and one 1500W electric heater we are keeping warm enough. We both like it a bit on the cool side so we keep the thermostat set to 66 degrees and have comforters to snuggle under while watching TV at night.
Fortunately the weather is warming and things are melting which we are glad to see since it's our grandson's first birthday and we are looking forward to our guests being able to attend.
Next time you hear from me I'll probably be complaing about it being too warm. Sigh...