Developing passive income is different. With the exception of one of my passive income streams (cryptocurrency mining), all of the others require real, hard work. Truly, I understand the barriers for people getting into building alternative income streams. I would say that most people WANT passive income, but truly aren’t willing to put in the blood, sweat, and tears to make it happen.
The most liquid of the private investments are investing in equity or credit hedge funds, real estate funds, and private company funds. There will usually be 6 month – 3 year lockup periods. The least liquid of the private investments are when you invest directly into private companies yourself. You might not be able to get your money out for 5-10 years, depending on the success of the company and upcoming liquidity events.

One of the best ways to build wealth is to get a handle on your finances by signing up with Personal Capital. They are a free online platform which aggregates all your financial accounts on their Dashboard so you can see where you can optimize. Before Personal Capital, I had to log into eight different systems to track 28 different accounts (brokerage, multiple banks, 401K, etc) to track my finances. Now, I can just log into Personal Capital to see how my stock accounts are doing, how my net worth is progressing, and where my spending is going.
Portfolio income can come from multiple sources – interest/bond coupons, stock dividends, financial strategies including derivatives and capital growth.  Each offers some cash flow and some also offer potential capital gain with some risk from liquidity and volatile prices.  In this low-yield environment, many investors rely too heavily on cash flows and to pursue this are venturing further into riskier areas than they’d normally consider.