If you do significant dry camping so you have to rely on your coach's batteries I would encourage you to install a shunt based battery monitor. This will let you know how many amp hours of DC power you are really using.
There are several types available. On the high end is the Victron line. Their smart shunt doesn't have a display, but uses a Bluetooth enabled app on your phone to display and store amp hour data. Renogy has a good one too.
On the lower end is the QWorks battery monitor for $45 on Amazon:
https://www.amazon.com/QWORK-Battery...2-d605505c9d1e
It is a basic battery monitor that shows amperage, voltage and cumulative amp hours used.
I replaced the OEM batteries on my new Axis with a pair of 100 Ah AGMs from Amazon made by WindyNation. They have worked well for me and allow me to go 3+ nights of dry camping and stay at or above 50% for best life.
David