Your answer let’s me know that it can be beneficial even if one can pay cash. 

I know his situation because I got introduced to him by a mutual friend.

Ive seen you in the REI Groups on FB how beneficial have those been for you? 

Think of a REIT as a mutual fund of properties (usually commercial properties) where you are delegating the management task to the executives running the REIT.

Frugal living is definitely nonnegotiable, but I am wondering if it would be more lucrative to live frugally and pay off my loan ASAP or if it would be more beneficial to drag that loan out for ten years and increasing the overall interest paid while house hacking ASAP. 

Thanks @Philip Smith no IT is actually our mutual achilles heel!

I would like to know what your experience has been/ is it more beneficial for to take the online courses they offer since I currently work full time

Not only does it add a layer of protection for the you, the property owner/investor, but it's also beneficial to them both now and as they take their next step in purchasing a home (depending on the company they can receive discounts for having prior insurance).

The price points have to be beneficial to the investor.

With checkbook control you will not need custodian approval to purchase real estate, invest in precious metals, execute trades on stocks, bonds, or mutual funds, or even buy cryptocurrencies (we do recommend caution when investing your money with this freedom, but it is your money to spend after all...)