They ones that need new roofs, have broken pipes, no heat source, or have water damage.

This is a sometimes a difficult concept for non-contactor to grasp but:  The Customer Always Pays For EverythingContractors do not have some secret source of funds - every dime they have or spend or make is obtained from the customer.  

Every single sponsor on the planet is trying to diversify their equity sources, even the ones that supposedly do not take money anymore like Baupost Group (Seth Klarman).

I’ve observed that those who actually seem to have time freedom achieved through real estate have done two things:1) Built up a $1.5-$2M portfolio at minimum.2) Paid off said portfolio.It’s the accumulation of wealth, yes, but also the lack of leverage that, per my observation, seems to be the source of real, lasting freedom.Sure there will be plenty of exceptions, but most who aren’t in this spot are simply working in the business of RE, in some form or fashion.

That will be your main sources of funds...and typically you and your friends will need to invest $50,000-$100,000 per person. 

In San Diego over the last 10 years I have had average rent growth on some years of $700 (source core logic) and I believe every year has been over $100.Virtually all MLS properties in my market bleed cash.  

I just recently bought my first house so cash is kind of tight but I want to add sources of cash flow more than ever now that I have a mortgage.

Paying down a mortgage does not increase cash flow it simply shifts the income source from the property to the equity.

However, since private lending is  likely THE source of real estate investing financing for the short- and mid-term future, it would be well worth the effort, I'm thinking.

I'd love to source your next deal.