Found a good toaster oven at a local thrift store yesterday for 19.99 so i had to pick it up even tough I am not powder coating at this time. This one is large enough to hold a normal size cookie sheet with room to spare on both sides.
I set it to 400 and walked away for 10 minutes, when i came back it was at 400 degrees
I set it to 425 and it went to 425, then set it to 450 and it went to 450...
Now that I have a toaster oven that works and is actually accurate, I can powder coat or heat treat without issues.