They have offices in a number of cities obviousl

They have offices in a number of cities obviously for marketing and other functions. Theoretically, as you say, any of the companies supplying components, much like QMC making QD at their labs, would be doing their work at their own premises. Once a product is ready for production, FF would either manufacture themselves, or contract it out. Freschfield not having big offices teeming with people is not a necessity. QMC started out the same way.