Ask HN: Manufacturing somewhat novel MIDI controller

Thank's in advance. I'm a SW Dev, total virgin when it comes to hardware manufacturing. If I want to make(for the masses, not just for myself) a somewhat novel midi(pluggable via usb) controller ("piano" keys plus a few control surfaces, nothing new but combined in a new way) what kind of expences(on the hardware side, let's exclude software for now) can I expect? Is it doable at all (may be all the half-decent piano keys are not available / patented / whatever)