I bought a 2017 EXISS stock combo trailer. The first thing I did was install 2 interstate deep cell battery then changed all intiour lamps to led lamps then I instaled 2 2000 what solar panels in sires put a morning star contorlor. in it is a prostar 30 . took trailer on a 6 week trip this spring run lights heater fridg all with no dead battery . the prostar controler keep battery at 13.5 volts down to 12.4 volts.