Originally Posted by Akcontender
.... How many cranking amps should I look for?
None, you are not cranking the engine with house batteries except in the rare case your starting batteries are run down.
GC2 batteries are about $88 at Sam's Club or Costco.
There are 12v starting batteries. Then there are 12v marine batteries like on my sailboat. A compromise used for starting (hopefully not on very cold winter days) and deep cycle for nav gear.
Flooded golf cart batteries work fine for house loads but require periodic maintenance such as adding distilled water. 4 GC2 batteries will supply enough capacity to run a microwave. How often you have to charge them depends on your power usage.
I run my generator once a day for about an hour if the weather is nice and 2 hours if it is cold enough to run the furnace.
How do you know your batteries are almost done for? Last summer I was boondocking and was not able to run the microwave. I was pulling a battery to take to be load tested and noticed my terminals needed cleaning. Problem solved.
Just got a load tester from Harbor Freight for $20. While adding water, I also checked my 4 yo house batteries. They are fine.