Some good writing here! I am a realtor myself and frequently get in touch with clients that consider buying a realty estate a conservative of investing. I once heard of a transport company in Vienna, Austria, which focused their entire profit on buying eventually every house available in the downtown for about 80 years. That must be some of a passive income!
If you watched the video, he goes into a discussion about shocks (about 8 minutes in) like bad investments but how they don't really matter as much if r (rate of return) is greater than g, the rate of economic growth. If r = 5% and g = 1%, then you can lose 80% (the difference) and still be ahead because the return on the remaining 20% has paced with economic growth.
That got me thinking how many people in our country cook some amazing things, but never capitalize on it. So if you have people at home who cook some speciality and you feel that it will loved by people in your city, you can start pickup service at home. Get the order, prepare the food , opt to deliver at home (at extra cost) or ask them to pick up from your place. And if you are thinking about preparing “Andhra meals” in Pune, I am your customer already.
There are many success stories you’ll run into of what it takes to generate multiple streams of income. However, one of the most important tips is to take on multiple clients. One client being your income source is bad news. They could voluntarily or involuntarily leave you high and dry. For instance, their business may begin to suffer and they no longer have the funds to pay you. Well, that is your income stream; gone without warning.
I knew I didn't want to work 70 hours a week in finance forever. My body was breaking down, and I was constantly stressed. As a result, I started saving every other paycheck and 100% of my bonus since my first year out of college in 1999. By the time 2012 rolled around, I was earning enough passive income (about $78,000) to negotiate a severance and be free.
One of the most appealing options, particularly for millennials, would be #12 on your list (create a Blog/Youtube channel). The videos can be about anything that interests you, from your daily makeup routine (with affiliate links to the products you use), recipes (what you eat each day) or as you mention, instructional videos (again with affiliate links to the products you use). Once you gain a large following and viewership, you can earn via Adsense on YouTube.
There are a ton of ways to diversify your investments, some of which can send real income your way. By opening a brokerage account and investing in ETFs or mutual funds, you can earn real returns you can use to supplement your income. Of course, the flip side can also happen – as in, you can lose money. So, make sure you understand the risks before you dive in.

Great ideas here, and thanks for the link! I’m definitely interested in learning about using an Ebay store, although I’ve heard they are not as effective as they used to be. One interesting problem that arises though is with online work, that is, work performed via the internet. If one does not reside in one’s home country while doing it it might be considered illegal (so check on all those tax implications).
Stocks (shares) paying dividends are typically a reliable source of income but they have higher risk of capital losses than cash and bonds. So, it’s wise not to chase yield indiscriminately.  The 10 highest yielding stocks on the ASX 200 (the 200 largest companies in Australia) are shown in the table below.  But their share price performance on average over the last year has been underwhelming, as shown in the far right column: