I installed an el cheapo dorm refridge/frzr (Lowes - $100 or so) and used it on a 6-month Great Circle Loop trip a couple of years ago. I added no insulation
just stuck in in a cabinet and plugged it in an AC outlet on my small catamaran
. (I have a 1000w Heart Inverter
, and twin 120ah AGM
batteries for the house bank. )
We motored most of the time (can't sail the GCL) so the twin engine
alternators kept the house bank up.
It did a nice job. I couldn't spend days on the hook with this arrangement but if I added insulation
to the top, back and sides, I'd bet it would cycle less.
Do your electrical
sums, battery/s capacity, 'hook time' , yada yada yada --
But for $100 I couldn't beat it.