As far as your batteries go, I use battery tenders in storage. I put one tender on the chassis batteries and one tender on the coach batteries. That way the all batteries are maintained and not overcharged as the inverter/charger tends to do. You can purchase the tenders at Walmart ot any auto parts store. They run $26 to $50 each and charge at a rate of 1 to 2 amps. The only requirement is your batteries must be at full charge when you connect the tenders as tenders are not chargers only maintainers.
Marty Christensen
Contessa, 08, 400HP