I'm having trouble with the "living aboard is hard on batteries" statements.
We've lived aboard most of the last 14 years. Our first set of 8-D gelcells lasted over 7 years, our 2nd set of T-105s lasted another seven years, and our third set is now four years old and in great shape.
We do have 500 watts of solar
power, mostly live on the boat at 32 degrees N or further south so get good daily recharge rates and never pull the batteries down below 80% charge (-125 amp hours) and usually don't pull them below 90%.
controller is set to charge our lead acid T-105s to 14.5 V and they do reach that voltage almost every afternoon and then float at 13.65.
We have a 9 cubic refrigerator and run a Technautics CoolBlue ACC refrigeration
system. That uses a BD-30 (I think) with a modified controller. The compressor
pulls 3.5 amps at 14V.
We NEVER turn on the AC shore power battery charger.
It has never occurred to me that living aboard
was hard on batteries!