[Former StClairSailor]

We had a 30' sailboat for years and were fortunate enough to have shore power when on dry dock. Kept it plugged in to trickle charge the batteries. We do the same now with our 5er for the time between summer camping ending and leaving for warmer temps at the beginning of the year. I blow out the lines, empty and wash out the water heater, put AF in the p traps and toilet, empty the fridge and leave the doors on it slightly open to prevent mold.