Looks nice.
You know, if it WAS only $150 or even $75 of materials, so what? You sell it for what the market will bear. Who else offers one like it? No one? So sell it for more. Plus, time to think it up, to develop it, and produce a complete finished product are all part of the deal. Sell it for what you can get, thats cool. And, again, it looks nice, quite nice.