Obviously he had to design the board completely including the case, plate, PCB, caps. Then he finds a factory to outsource the work to for mass production. It's a lot more work than you think, he's been working on that layout for a few years. A lot of these questions should be fairly straight forward. Think of it like any other product because no matter there will be research, development, and production, it's not like he's making them all by himself.
If you're in it for profit then you're in the wrong community imo, we're here to help each other out.
