I used 2 fridges. I have a Snomaster traveler 35l - the cheapest in the lineup. As opposed to its bigger more expensive brothers, this one is made out of plastic and with thinner insulation. The fuse holder gave up second trip, I took it apart and rigged an inline fuse. That was sorted and it held, no issues after. The problem was that because of the thinner insulation, it was running a lot,. On top of it, back than I had an AGM with a simple VSR, so the battery was never full.
I saw on offer an engel 40 l, it was a really good price during the COVID lockdown , and I took it, and also installed a redarc DC to DC . The combination of lower amps and the better battery charge was like night and day, now the battery actually became overkill, so I was able to get something a lot lighter and smaller.
I still have the Snomaster in my house, it is running non stop for some years now.
My point is : if you lack space and weight is problem, a more advanced fridge allows you to go with a smaller auxiliary battery, or even no extra battery and just a solar panel to top off the starter one.