The most under served part of the real estate property management field is the smaller under 4 unit buildings and you can use this part of the market place to build a portfolio of references.

He is willing to do a mentorship of sorts as this was his final house to sell in his portfolio and my first.

I don't want to back myself into a corner where I have a portfolio of rentals and can't even purchase my own home.

With a large building your management costs are lower than a portfolio of single family homes all around town, and your more protected against vacancy, because even with 1 or 2 units empty others will still be providing some cash flow.If you want to be more active you could buy a single family home at a deep discount, rehab, and resell for a larger profit but this requires much more involvement.

For me the end goal is to build a portfolio of passive income that will enable me to permanently depart the rat race and do what I love without feeling any heartburn.

My ultimate goal is to work towards a small portfolio of rental properties for the cash flow.

My goal is to create a real good cash flow portfolio.

Hopefully, I can grow my portfolio and pass it on to my children later in life.

Is your portfolio suppose to be made up of a paticular percentage of assests for this?

It will happen to you often if you build a portfolio, welcome to real estate investment :-)