Just about every town has a used appliance store. Our local one sells refrigerators for a hundred bucks. Also, try Salvation Army, Goodwill or St. Vincent DePaul stores for used refrigerators. If they have an above freezer, that's just a bonus place to flash freeze veggies before you freeze them, or a good place to keep popsicles or ice-cream.
We used to have an upright freezer. I hated it. After 20 years, I traded it for a chest. You can't put as much in an upright as a chest because stuff falls out and every time you open the door the cold air falls out on the floor and it has to run to catch up. A chest is a better option, more economical to run and holds more.
I suppose if you just run either at the lowest temp it may never freeze. Don't know for sure.