For turnkey properties (given your $20k constraint) it may be difficult to break even on cash flow within 2-3 years.

While each market - real estate and stock - has it's own risk/return profile, the comfort of owning a cash-flowing hard asset becomes more and more appealing when the stock market gets choppy. 

I am not sure which market to look into as right now I am currently in new york and was told my best bet for cash flow would be to look oos for deals that I could use as a rental or house hack.

As soon as you go into nicer neighborhoods people are smart enough to not get themselves in a situation where they get super motivated to sell their house fast for cash and also smart enough to bring it on market instead of doing a back door deal with a wholesaler.

Easiest is offer cash for keys.

Cash out less than 75%

Since I can borrow money and get cash flow and beat inflation by buying properties, why would I buy treasuries?

When starting out, but owning an entire property outright with added improvements, would it be better to cash-out refi or get a HELOC? 

That way you can reduce your living expenses and get cash flow from it. 

I understand that there are many state legislatures where similar laws are advancing.