If musk can do with his cars what he did with spacex he will be able to produce items for his vehicles himself and overcome the fixed cost dilemma. I recall him making some of the parts for his vehicles in the spacex plant. Most of (90 some percent) of his rockets are made in house, which is why he can undercut orbital, lockheed, and the russians by a factor of 3. Last I heard theyare building a tesla manufacturing plant in san jose. Let's wish them luck.