In order to supplement my education, I started watching Youtube Videos on Investing topics such as: finances, stocks, precious metals, commodities, Rich Dad Poor Dad, building wealth.

You will need to be able to afford to supplement your tenants rent long term.

I would like this investment to supplement my current income, and over 10 years build a sizable real estate portfolio that will allow me to leave corporate America and spend 100% of my time focusing on growing my units.

For a "sponsoring business" for the SD401k, your friend can simply sign up to be a distributor for a great product (such as a nutritional product, for example, there are thousands of possibilities).

And if you are trying to supplement your income with rental property, its gonna take a few units to make much difference.

This would just be a supplement to those funds for a project. 

Here are my two cents:If you stay in Indy you will essentially be walking away from an income which can be good if you know that you will be able to put together a strong deal flow which will supplement the lost income, and the increase which you would have achieved should you have taken the job out here in CA.  

So pretty nice supplemental income.

I am currently an electrician and hope to have a few rentals when I retire to supplement my retirement.  

It could be a nice supplemental income and additionally great exposure for a new/advancing investor.