does that same thing. They would be your key competitor and they sell those boxes for $200 at Walmart. Unless you can build and sell them for under $200... It might not be enough profit for a small operation. You really make much more building gaming rigs. - Higher end means more margin.
Also there is no such thing as a 'foolproof system' - no matter how good u make it, people will get confused. - just imagine - "i bought this Kodak photoprinter at walmart and the CD doesnt work! WTF?" (here is where you try to walk them through a CUPS install for a printer which has no driver in Linux)
So for the money that you would make I would say "bad idea" - especially when you can make $20-$30 and hour telling people how to set print margins in excel.