> The cost of development for the Falcon 9 and Falcon Heavy were incredibly low
Which is to be expected since governments spent on the order of a trillion dollars and 50+ years developing the technology. Just about every aspect of their operation was conceived, developed, and trialed before Musk was even born.
SpaceX deserves a lot of credit for refining that tech, but do not dismiss the fact they are standing atop a mountain of taxpayer funded R&D without which they wouldn't even have a business model, let alone working rockets.
=Smidge=