If I were to leave my home tommorow heres what I would do, fill water tank about 1/2 full, turn on heat, always have LP tank full, turn on switch for blower thats located on water closet connecting wall, as furnace cycles on and off the blower in foil tube from furnace will cycle with furnace also. This will keep all tanks warm and plumbing protected also. Just make sure the openings for water hose and sewer hose are closed.
Have done this with all 3 coachs when we went to Florida Feb vacaton week many times.
If you come back in cold you will winterize when you get home leave furnace running until you can do this.
Have a safe trip and enjoy.