Thanks for the offer ( I might take you up on it ).
I do not get the batteries for free but dirt cheap 80.00 no matter what I get ( except the 12" yellow is like 96.00 ).
Yes the fridge would be the only thing drawing overnight. I normally only run the lights ( incl the rear ones ) with engine running.
Not sure I will go all the way to 4 batteries, but dual for sure.
My inclination for the dual Blue was based on the long run as you put it as well as the double post on top, as when I had my dual Yellow/Blue, the double side post was uselless as the space under the seat was sort of limited with 2 batteries
Ron, the Blues have 2 years, but in the program I get them, they do double the warranty up to 4 years, so no matter what I get , I still get 4 years ( but that extension it is not transferrable )