This isn't the sort of thing to do as a cold startup. The way to do this is what is sometimes called "intrapreneur", as a "startup" within an existing large cor

This isn't the sort of thing to do as a cold startup. The way to do this is what is sometimes called "intrapreneur", as a "startup" within an existing large corporation that can bankroll such a large project. Are you an engineer, or a banker? If you don't have a track record in the banking industry, you're hosed. No one will give you that kind of money. If you've actually been there for the founding of a bank before, then maybe. Moreover, if you're an engineer without banking experience, you probably have no idea what you're getting yourself into.