I picked up a $10 thrift store bread machine and a $20 Wagner Heat Gun at Home Depot and made myself a pretty awesome rig that can do 2 Lb unroasted at a time. I hardwired the motor to a light switch for constant motor rotation and bean agitation, and cut a hole in the top of the bread machine for the heat gun to sit in. I took the bread machine heating coil out entirely, and all heat is supplied by the heat gun. Typical roast takes 13-19 min depending on what I'm aiming for. I normally roast 20 oz at a time but I've pushed it upwards of 40oz before with success. It takes a while to master positioning the heat gun just right at each stage of the roast for a smooth roast profile, but once you get it down, you'll be roasting some fantastic coffee. I use an adjustable lamp with a hole cut out in it to keep the heat gun at the right heights during the roast, and cool by blowing air from an air mattress pump through a hose into a rectangular frame with a screen in the middle so the cool air is forced up through the beans. Everything sits on a wooden "tray" I built with handles that I can lift up and carry in one piece.
As far as customer support and parts go, if you build the machine you'll know how to fix it. If the bread machine gives out, you can grab another at Wal-Mart same-day or Amazon-Prime ship it. Same with the heat gun and basically anything else on the machine. Heck, you could just build two machines or three or four or five for $60 a piece.
The machine isn't pretty, but I've spent less than $40 on roasting equipment over the last two years. If you're willing to put in a little creativity and elbow grease, this could be a great option
