Investing in coins and collectibles: Buffalo nickels and Spiderman comic books are good examples of coins and collectibles that can rise in value, and thus offer opportunity for passive income investors. You'll need to get up to speed on the value of any coin or collectible under consideration, but once you do so, you're on the way to price appreciation on a commodity you'll be paying a lower price to buy, and will garner a higher price when you sell.

Passive income differs from earned income and portfolio income in a variety of ways. Passive income is generally defined as a stream of income earned with little effort, and it is referred to as progressive passive income when there is little effort needed from the individual receiving the passive income in order to grow the stream of income. Examples of passive income include rental income and any business activities in which the earner does not materially participate during the year.

One of the benefits of the time we live in is all the software and technology we have available. If you want to scale a business that’s bigger than yourself, you’re going to need systems in place to get you there. These systems should involve automating as much as you can. The less involvement of you in the day-to-day means you have time to focus on the big picture strategies that help your business grow. 
Creating multiple streams of income does not mean get a second job to supplement your current income. A second job does not provide you with the flexibility and freedom to increase your income. In fact, it can hurt you when you think about it. You are trading time for money and in the long run, you lose. Instead, create something that will allow you to give yourself a pay raise when you need and want it. 
For a person working for a wage, their source of income is their job, or their labor (aka their time that they sell to someone). But you can own a house, and rent it out, and when your renters pay you renter every month, the source of that income check is your rental property, or your house. It would just be called rental income. If you have money in the bank in an account that pays interest, those interest payments are another source of income. We can say the source is interest payments, or we can identify the asset that is generating rent, and say your money in the bank that is generating “rent” (aka interest) is your source of income.