Second battery in the Kia would be the most obvious answer. Could have it all installed with top notch gear for ~$700, or DIY with basic stuff and a good battery for under $500.
ARB have a Fridge that draws less than 2.~ AMPS/HR, just to throw a spanner in the works of your descisions
Not sure on price though.
Life's too short to be grumpy, SMILE
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