Rocmoc, I think most DP have 4 batteries if it has a propane/electric fridge. Our previous all electric coach had 8 house batteries and 2 chassis batteries. I hated checking all the house batteries and filling them with distilled water. The wet cell batteries would outgas causing a built-up of crud on the posts and battery pan.
So, 6 yrs. later on the original batteries, I replaced all of them with AGM's and could not have been happier. Wish I had done it earlier as they were so clean with no fuss! We got 1.5 yrs. using nice clean batteries before I sold the coach this past November. I think that helped us on getting a better price as we had newer batteries compared to other coaches on the consignment lot. Now, it was not cheap, but worth every penny to me as they stayed so clean.
If I were you, I wouldn't take used batteries to a 'new to you' coach. I'm not sure how long you plan on keeping your current coach but batteries only last about six years or so. If I were to get a newer coach, I would replace those batteries with all new ones so it will take you farther into the future and you can enjoy the new batteries. Putting old batteries in your old coach might affect the price that you get.
Good luck,
MM.
Mr.Mark
2021.5 Pleasure Way Plateau FL Class-B on the Sprinter Chassis
2018 Mini Cooper Hardtop Coupe, 2 dr., 6-speed manual
(SOLD) 2015 Prevost Liberty Coach, 45 ft, 500 hp Volvo
(SOLD) 2008 Monaco Dynasty, 42 ft, 425 hp Cummins