IF the fridge is built into a closet chose one i that vents instead into the cabin area , not back into the confined space.
It is worth what extra you will pay for a modern machine with a 12V Danfoss compressor.
IF and only,, IF,, you plan to cruise and spend much time at the hook.
A house cheapo will be $75 or $100 in small sizes and not spin the marina meter hard , but the extra thousand spent on a genuine modern RV / marine unit will pay for itself by not needing a thousand bucks worth of batteries .
How you will cruise counts. Pay now or later!