i'm building a system with 3x200w panels because thats all I can put on the roof of my van... i'm looking at going with renogy 200w panels and a renogy 40 or 60A MPPT to start and adding a DC-DC cvonverter as suplement... suggestions? i've already got my Big Battery 202ah lithium battery and i'm trying to get my system to use the least amount of battery in the day and most at night because it gets cloudy here for days on end sometimes in washington state...