A very astute business associate and close friend of mine who runs a real estate development company once said to me: "Take a look at the Forbes 400 list of the wealthiest Americans, and notice how FEW of them made their fortunes in real estate."
This was a guy who made a killing back in 2007 when he bailed out of all his residential projects right before the crash.
I’m a real estate investor and real estate has been very good to me for almost 50 years. But the huge money lately has been made in energy and tech.
I’m a gnat compared those guys but I’m very comfortable thanks to real estate and energy investing.
The billionaires appear in most cases to have made their money in (offshore) heavy industry or to have won the software Gorilla Game in the 90's.
But I live in an area with many, many multi-millionaires - and almost every one I talk to made their money in commercial real estate. It's the most straightforward way for someone without an Ivy League education or DC insider connections to become successful - especially since the Forbes 400 billionaire caste has been careful to buy enough government regulations to lock the barriers to entry behind them. :)