Fridge and stove.

I have had the thermoelectric fridges, as you suspected they aren't worth having in the summer and hard on batteries.

Next I did the inverter and dorm fridge. Worked OK, the biggest downside is that the truck beats them to death. Also hard on batteries. I had a couple before I gave up and bought a dometic 12 volt fridge. They have a smaller one than the one linked to 1.1 cubic feet I think. You can find them at camping world. Just over 3 years old and never a problem, can leave on for a few days without starting truck.

For a stove you can get a single burner butane stove super cheap. And cook outside the truck.

 

Koolatron has a 12 volt thermo electric cooler with heat pipe technology they say. It has small amount of Freon inside it. I had it for 5 years before I got a truck with a built in fridge. It has a temp setting and a light inside. I got mine off amazon but I seem them at pilot etc for around 200 sometimes 150 on sale. I loaded it down and it kept everything plenty cold. Also had 2 of those portable 12 volt stoves. I couldn't have an inverter and I cooked everything and anything in them. Took about 30 min to and hour but it would cook raw meat. I ran that setup 4 years pulling intermodal for hunt who was gay about inverters. New company has a big fridge and microwave built in. Has made life so much easier.

 

I ran a Coleman Powerchill for about three years, replacing fans every 6-8 months or so.

Then, with last year's tax refund, I got the Truckfridge TF-41, which is actually an Indel B (not even rebadged). I keep mine set at 23 degrees (yes, below freezing), and it keeps my frozen dinners, well, frozen, and it'll freeze a couple of half liter bottles overnight for my small drink cooler. Drinks kept near the lid generally take a day or two to start to freeze. If I didn't want to freeze water bottles, I'd probably run it around 28 degrees; that keeps frozen stuff frozen, but doesn't really freeze drinks.

Best $500 I've spent in a long time...

 

I have similar induction cook top from wally. It will not work with cheap truckstop inverter. Need or true sin inverter or generator