<i>"The rule of thumb for anyone building hardware is that a product will sell for three to four times that of material costs, Cyril Ebersweiler, the founder of the hardware accelerator HXLR8R told me. “That would be at least a $100 product if you were only selling the Pi,” he said."</i><p>3x to 4x material costs? Is that retail? What about selling at just above cost and charge these rates for the software?