If you need cash flow, and the dividend doesn’t meet your needs, sell a little appreciated stock. (or keep a CD ladder rolling and leave your stock alone). At the risk of repeating myself, whether you take cash out of your portfolio in the form of “rent”, dividend, interest, cap gain, laddered CD…., etc. The arithmetic doesn’t change. You are still taking cash out of your portfolio. I’m just pointing out that we shouldn’t let the tail wag the dog. IOW, the primary goal is to grow the long term value of your portfolio, after tax. Period. All other goals are secondary.

Nearly every “9 to 5” worker (nothing against them) is a service worker. The definition of a service is a commodity where the value is created and consumed at the same time — think massages, for example. They create value — inputting purchase orders, serving customers, managing employees, etc — for a company or employer. The employer then consumes these services simultaneously.
Add Leverage (Mortgage) and you greatly increase the ROI especially from the perspective of using Rents (other peoples money) to pay down the mortgage and increase your equity in the property over time. At this point then yes price appreciation is secondary bonus and we have an arguement of how and why Real Estate can be better than Growth Stocks in some scenarios and for some investors.
There are dozens of ways to generate passive income. However, the option you select has to do with two metrics: time and money. Either you have a lot of time or a lot of money. Most people usually don't have both. But, if you have a lot of money, generating passive income almost instantly is easy. You can buy up some real estate and begin enjoying rental income. Or, you can invest in a dividend fund or some other investment vehicle that will begin generating a steady income for you.
I actually spent a year and a half working as an affiliate marketer (mostly selling drumming related products – lessons, kits ect). 5 years on and one of my one page sites (which I’ve not touched) still nets me about $150 a month. I won’t be retiring off that but only really now appreciate the reverse pyramid approach to entrepreneurship (working for nothing initially but later being paid without effort!)
If you have specialized knowledge in a certain topic, you can put together an online course to teach others. For example, if you have experience in real estate investing, you can create an online course “Real Estate Investing 101”. The benefit of an online course is that once you create the course material, you can sell it to as many people as you want.
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