Greetings & Welcome!
Mini fridges are usually a much better choice than the expensive 12v compressor fridges unless you can find a 12v dorm fridge that uses a wall wort to convert shore power to 12v.
The biggest problem with them is the inverters needed draw power even when not in use. This problem can be solved with a temperature sensor, and a relay installed between your battery and the inverter. With this setup, the inverter only runs when the fridge runs.
You’re probably going to want to double your solar. Short and cloudy winter days cut solar production by 75%+ from during the summer. I strongly suggest you add an isolator to charge while driving, along with a generator and a battery charger. Most full timers have ditched solar all together.
Cheers!