Gold is not an investment but just a hedge for a global currency collapse.

It's now currency!

We can debate things like structuring your portfolio with seller financed loans with the intent to default when the currency deflates.

He also mentioned transportation companies, commodity producers, large currency exchange transactions (whatever that is).

For ex) a $100k initial investment.

I have had a long career in institutional real estate (office/tower leases for Sprint for ex) in addition to practicing law all with the same objective that you have.  

Keep your seed capital close, and perhaps invest in a foreign currency that may not be as badly affected by an impending financial crash. 

I would say you get the best return on investment properties, but again that all depends on the acquisition price, property management, repairs, rental amount etc..As far as stock I'm hearing Mutual Funds and Forex. 

I Publish a Forex Trading Educational site.

I had included utilities in the rent on a condo I own, and the tenant was mining crypto-currencies.