Regarding the battery...
Just got back yesterday from Moab. We have 3 LiPo batteries and 200 watts of solar. Based on our usage, we could definitely last through 2 days of completely cloudy weather and could probably last through 3 days. With sunny days, 1 battery will be totally fine - it's just the risk of continuous completely cloudy days (as Sunday through tomorrow, apparently, will be in Moab) that you have to worry about.
The night before we got to Moab, we were in Colorado and the temps dipped to 21º - we were down about 50 amp hours in the morning from running the furnace all night. Using the furnace draws both electrical power to run the fan as well as propane. What we learned:
1. Lower the top at night as you go to sleep - there's plenty of head room to sit up and lay in bed with the top down and it's much, much more heat efficient with the top down.
2. Set the thermostat at 60º instead of 70º - there are no numbers on the thermostat, so you'll have to experiment to see where it comes on. We have a indoor/outdoor thermometer that we use to tell what's going on (it can capture the minimum temp over a period).
3. The night in Colorado, I'd guess that we used almost half of a 20 lb tank pf propane - the furnace seemed to be on 40% of the time. I haven't refilled the tank, so I don't know how much we used in Moab although the temps never got much below 40º there.
Forgetting the outside (rock) lights on can use 10 amp-hours overnight if you aren't careful.
The fridge will generally use most of your battery power - haven't been in enough 80º days yet to have a feel for that. Keeping the interior "hatch" to the fridge compartment cracked will probably keep the heat from building up in the fridge compartment though.
More on storage shortly...