I'd buy a small newer (post 1979 construction so no rent control) rental property in San Francisco. With that much down you should be able to get it cash flow positive plus increase your equity at the same time if you needed to liquidate.
I realize this is San Francisco we are talking about but the idea that $1,000,000 is merely a down payment for a small living space is mind boggling to me (yes, I live somewhere much less desirable and much cheaper).
I think what he means is that with $1MM you'd be able to pay off a large chunk of the house which would reduce the amount of interest owed. It doesn't necessarily equate to just being a 20% down payment.