For example, if there are mechanical parts, you can go to a machining company to make them; if there are circuit boards, you can look for PCB printing companies to order them; and finally, there are housings, which you need to find a way to make out of materials like plastic or metal. You can't have a small company that encompasses all of the above production lines. As long as you have the technology and money, most of the work can be let other companies to do for you.