My initial goal is to develop enough passive income to pay my monthly mortgage payment, and then grow from there, depending on where things go and how scalable I can manage to make the workflow. 

I have recently discovered the scalable strategy of private lending.

So if I take my cash on hand to buy a primary home, then it slows my construction scalability.

Scalability it probably wouldn't be great for me to personally do it.

As you start closing deals, you will need to reinvest your profits into mailing lists and other scalable activities to grow your business.

Michael Blank and now Doug Marshall describe commercial real estate as a great investment with a lot of potential for scalability. 

Very robust and scalable.

None of that would matter if your client was buying or controlling property using Seller financing, leases, options, or subject to purchases.Commercial lending is great, but should not be anyone's only strategy as it restricts scalability.

Scalability - Grow quickly through creative agreements with landlords, furnished properties, biz credit and creative private financing (no mortgage necessary!!)

Outside of that assumption, the principle of limited scalability still stands true.