I second the residential refrigerator approach! This completely eliminates the danger of an appliance fire, and gives better food storage performance, particularly for frozen items. You will need to limit how long you can dry camp without using the generator, but a good battery bank and efficient inverter will give you quiet night times and keep things cool when in transit. My motorhome had a 23 cu ft side-by-side unit from the factory, and was ideal for full time live aboard use.
2007 Tour Master T40C
Acura MDX toad
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