Roger,
See if the batteries are maintenance free. If they are it will say it somewhere.
I have replaced my bus batteries twice in the last 16 years, and they lasted about 6 years. I never checked or added water. I had a somewhat lazy attitude about them because before complete failure I had an on-board 24 volt charger/converter that could (and was) used to give them a charge when they started to fail. If you have no built in charger for your bus batteries you do have to be very much aware of your bus battery age and condition.
On your Liberty Elegent Lady you actually have two fall back positions in the event your bus batteries die on you. You have a built in charger (it is above your batteries) and you can jump the 24V bus battery system with the 24 V house battery system.
I wouldn't worry at all about your bus batteries if you know they are a young age. Once they hit about five years you do need to pay attention.