If you leave them hooked up long term. When you buy new batteries I wiould get a small solar charger to keep them topped off during storage. Nothing fancy just a simple solar trickle charger will do the trick.
the weight thing is a concern the Predator weights in at 2k got to carry water 120gal. X 8 =960 trailer is 10.5k, pulling this with a Duramax 2500 must weight about 6k has a GCVW of 22k.... Sounds like I am pushing it when you include food people other stuff... and the quads Hmmmm.