I’ve used standard propane RV fridges for years out in Black Rock Desert, Nevada in August and my ice cream was always frozen. You guys have my curiosity up, was it a more humid and hot environment where the propane fridges had trouble?
It sounds like that camper is set up to have a fridge, putting in the vented hatch isn’t that hard, nor is running a propane line. Remember you also need a roof vent.
What IS hard about installing RV fridges is getting them through the door! Often you have to remove the door frame from the camper.
My campers have always had ovens and they go unused. I wish I didn’t have it, a cabinet would be more useful. Those RV ovens are a little touchy to bake in.
I do use a microwave a lot in my camper. Big plus - it doesn’t heat up the whole interior. I use a 2000-watt pure sine wave inverter and a couple six-volt batteries. It’s a huge power draw but it’s only for a very short time.
If you do this, pay attention to the inverter type. Get a “pure sine wave” unit. Microwaves don’t function well on the cheaper “modified sine wave” type.
I bought a set of 2-gauge, 25-foot jumper cables just to get the wire (cheapest way to do it), cut the clamps off and used it to run a heavy duty charge line from my truck to the camper. Google “Anderson connectors” for the heavy duty plugs to use between your truck & camper.
You can fire up your truck for a bit of extra power while microwaving if you don’t bring a Honda EU2000... but don’t tell anyone if you don’t bring a Honda EU2000 or you’ll be booted off of the forum. :)