For years I ran 2 group 24's FWC's. We use our camper more than most folks. A 2000 purchased in 2000 Bigfoot that now has over 170,000 mi traveled. The 24's usually lasted about 2 years before they were down enough on capacity that mandated replacement. My battery compartment is not tall enough for 6'ers nor 27's.
I was sick and tired of removing them every 6 mo. to do watering and sooner for a big of desufation with my trusty old transformer type charger.. Good for 16+vdc.
So following the lead of Reddog1 I headed down the AGM path.
I decided to do the 1 battery 100ah lifeline thing that he had lived with for a couple of years already and did the following...
Installed a Wave3 for warmth... So the furnace is not used very much... (AMPAHOLIC)
Got rid of the Tube tv... Now led.
Added a switch to turn off the power to the radio.
Got a couple of led lights to read by... Expensive back then.
Ran my generator to maintain the battery and shore power... Also had the truck charging the battery when traveling.
We were able to get by with just 1 battery. Monitoring my trimetric to maintain a + ah by<>5% every couple of days when charging.
Then I installed all led lights... Wow
Finally I found an exceptional deal on solar....
Now we rarely use more than 15 ah a day.. and rarely use shore power when traveling nor the gen.... We have 3 data devices... Ipad2, Samsung S5 and a Macbook air that need charging. We usually watch 1-2 hrs of tv a night and read for 1-2 hrs.
1 100ah battery, no maintenance... I have had this Lifeline AGM for 6+ years now and it still has the same capacity as it had when it was new.
Jim