Whoa. Are you now claiming that the difference between prototype phase and series mass-production of a developed technology cannot be 90%?... On what basis? I'm less pessimistic seeing this:

"build a prototype in a government lab in hope of finding ways to lower costs"

That sounds nice, but competition with a sizeable budget brings faster development, large-scale production brings down costs by economies of scale.

_{*Lunatic*, n.
One whose delusions are out of fashion.}