Howdy. New Owner With Questions Not Found in the Manuals.

1) Why not leave it plugged into shore power 100% of the time?
2) Are you dumping into a septic system for the cabin? I leave my gray valves open until a day before dumping my black tank for flushing the line purposes.
3) Put a thermometer in it and see what temperature you are really getting.
4) Still not understanding concerns about batteries if you have shore power. Since you are living in the trailer, a generator of ocassional use would be the best solution for off grid power.