Leveraging the internet to create, connect, and sell is something every creative person should attempt to do. The only risk is lost time and a wounded ego. You can start a site like mine for as little as $2.95 a month with Bluehost and go from there. They give you a free domain name for a year. Forget all the add-ons. Not a day goes by that I’m not grateful for my site.
I also noticed that in your passive income chart at the bottom that you don’t include your internet income other than sales from your book. Is there a reason for that? Do you not consider is passive because you are actively blogging all the time to create it? Or do you just not want readers to know how much money you generate from blogging activities?
A different definition of residual income is that this is income derived from passive investments, rather than from a person's active income-generating activities. Examples are interest income, royalty income, rent, and increases in the value of investments held. Individuals typically work throughout their careers in order to build up a sufficient amount of this income to support them during their retirement.

1. The batting cage idea is very risky. I’ve seen many of them close over the years and it is not anything close to passive income if you want to keep the business going. You have to continually promote it and target youth leagues, coaches, schools etc to catch all of the new players who grow up and want to play. I’ve played at probably 8 batting cages over the years and 7 of them closed.
Residual income is when you continue to get paid after the work is done. This includes royalties from books, movies, or songs and also income that comes from real estate or business investments where you don’t actually have to be present to earn it. For example, Bill Gates is still making a residual income from Microsoft even though he isn’t working there anymore.
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