Congrats on joining the MH family. As to the RV batteries, there are normally two (3) 6V deep cycle marine batteries to power the coach and one (1) 12V Automotive battery for the chassis (engine).
The 2 deep cycle, also known as golf cart, batteries are fairly standard. Unless you and/or hubby are knowledgeable, I would have an experienced RV repair shop install them for you. Costs a little more, but less chance of frying your electrical system.
Good luck, and keep us informed with your progress.