Trying to "design your own" 24 V battery system to run 12 V appliances is NOT worth the time, trouble and expense.
AND....you won't know how many 6/12 volt batteries will be optimum for your RV.....until you actually GET one and see how much room you have for batteries.
There are only two things that you really NEED to run a generator for:
1) Air Conditioning. Just not possible/practical from batteries.
2) Charging the batteries. Good solar will reduce this but maybe not eliminate it totally.
I find that I need to run the gen only about 2 hours in the morning and 2 in the late afternoon.
And finally.....if you have a really QUIET generator, it won't be a problem anyway. Spend your power system money on solar and a quiet gen.
