Build one.
I butcher deer and make hundreds of pounds of jerky in a season. It's a matter of moving air with a slight temp....inlet and outlet. Very simple concept.
Find a stand up freezer that no longer works...or check the local Menards type of box stores for the defective variety. Brand new shell. Nice thing...just strip it of it's guts, or leave them in place, as I do. I build a small $25 window in on the front.
Drill a two inch whole low on each side. Drill a four inch hole in the top. Use something to block and control the outlet. (I have played with fans on the top, and just a license plate to adjust the outlet size. It takes some learnin... adjusting the flu, and the temps, moving the racks, etc...there are hot spots and cold spots...no biggee.)
Add a bottom plate of some sort, to set a hot plate on. I have used a few differnt things over the years. I really like this cheasy three pot crock pot. It had three seperate switches, so I could vary the heat considerably. Given it's in my shed with outside temps often below zero, the ability to adjust is good. This type of heating element should be under forty dollars. I bought two new shells at menards for fifty a pop over the years. I've built two, but can only feed one....lots of prep work per batch, one's enough, given all the other cooking going on.
I smoke my jerky on racks that are eighteen inch wide with quarter inch squares which fit my smoker. I can move the racks immediately from smoker to the dehydrator. I use 3/16 piano wire to hold the racks. I drill two holes per side for each rack, about three to four inches apart vertically. Really simple design. Two piano wires per rack. Twelve racks. Though it is better to use nine or less to allow the air a bit more circulation.
It's a highly functional deyhdrator for so many things, and can be built in a day, with few tools, mainly a drill and a three sixteenth bit and a couple of hole saws. I believe I have under two hundred dollars with racks and all. It's a killer tool to have on hand. Meat, veggies......large quantities, quick turnover.
If one has the space to build it. I have no doubt ninety percent of the folks here could build one with ease, and great success. It would be a great food saver, in a pinch, the heat could be adapted and the air flow completely void of power. I like a fan inside moving the air, but it will work without, just takes longer and needs to be tended to a bit more.