I would ditch the Not-So-Cold and install a RR frig, one of the best moves that I have made. My coach came with 4 (6v batteries) and down the road I may add 2 more but only when I need to replace the other 4. I did change out my inverter to the Magnum 2812 and new controller BUT the Samsung will run just fine on the Xantrex Freedom 458. My coach has been running on the inverter going on 3 years.
This is not my install but mine looks the same
Samsung Refrigerator Install
My Samsung 197 cost $1049 and $700 to have it and the Magnum installed plus the price of the Magnum 2812 and controller.
Now my beer is at 38deg and the ice cream is rock hard.