If time is money, then something like the SUNLU E2 may be a good investment. It’s expensive, but will do the job with the least amount of fuss. An air fryer is probably the best cost/effort compromise (note that the less expensive models may need to be manually restarted every couple hours). If you have a basic understanding of electrical wiring and you don’t mind investing a little labor in modifications, a cheap toaster oven and a PID controller is the least expensive option (well under $50).