[AZ Traveler]

Rodney,

I generally encourage folks to start with their battery bank and build out from there. You need to do a power analysis to sort our how big you want to go. Assuming you are building the system to boondock part of the time, I would consider adding 2 more batteries.

Your furnace blower motor is a power hog. A long cold night running the furnace 30-40% of the time would deplete a good percentage of the 200 AH you have.