I have a single, 85w solar panel which is wired directly to the batteries. There is, of course, a regulator wired between the panel and the batteries so as to monitor and control/regulate the charge applied to the batteries.
I ran a 20 ft 12AWG wire from the panel to the regulator and then to the batteries. Unlike most, my solar panel is not mounted on the roof. I really didn't want any more holes drilled in the roof in order to mount it. Instead, I store it in a slotted L-shaped holder which is fastened to the top of the storage compartment. I simply slide it out and place it on a "sandwich board" which I can move about so as to catch as much sunlight as possible. It does take a very small amount of "work and time" to do this but my wife says that it keeps me out of mischief in the campground. Otherwise, I'd just be sitting around having a cool one.
2008 Cougar 5th Wheel 27RKS
2005 2500 GMC Duramax