The Modern 12 volt Only units fall into two categories one is a peltier cooler. These have no moving parts with the possible exception of a fan and a thermostat and can also be "Reveresed" to become a "hot box" instead of a cold box.
They have fairly high amp draw for the amount of cold you get.
The other is what I call a "Danfoss" type device. Danfoss is but one company making the compressors in these units. Very high efficiency compressor units. Suitable for residential or RV. Generally draw about 3-4 amps door closed. add 2-4 amps door open due to the light.
I haven an Engel chest fridge/freezer 15 years old and still keeping things inside in the single digits.