Here's another example. If a person owns apartments that are rented out at a profit, they earn money each month without working a specific number of hours. If the owner earns $100/month net income from each apartment, the determining factor is how many apartments they own, not how many hours they work. Therefore, they may own 1 apartment and make $100 net income each month, or they could own 500 apartments and make $50,000 ($100 per apartment) each month.
In expensive cities like San Francisco and New York City, net rental yields can fall as low as 2%. This is a sign that there is a lot of liquidity buying property for property appreciation, and not so much for income generation. This is a riskier proposition than buying property based on rental income. In inexpensive cities, such as those in the Midwest, net rental yields can easily be in the range of 8% – 12%, although appreciation may be slower.

Peer-to-Peer Lending: Earn up to 10% in returns by lending individuals, organizations and small companies who don't qualify for traditional financing through peer-to-peer lending platforms like Lending Club. You can lend $100, $1,000, or more to borrowers who meet lending platform financial standards. Like a bank, you'll earn interest on the loan - often at higher returns than banks usually get.
One of the things I'm surprised your article doesn't mention is the tax advantages of this type of investment. The depreciation and rehab costs (purchasing distressed properties) can be huge deductions to ones income taxes, which none of the others have. Then, along with the appreciation of real estate, this passive income investment outperforms the notion of maxing out my 401k as well.
Buy a small business: A local small business, like a car wash or a laundromat, is a great way to put money down on a money-making venture. Automate it so you don't have to be on the premises unless you're collecting money. Go into a local business with your eyes wide open - study the books, especially on income and expenses, and examine water and utility bills if your venture will be open 24 hours.

Disclaimer: We spend hours researching and writing our articles and strive to provide accurate, up-to-date content. However, our research is meant to aid your own, and we are not acting as licensed professionals. We recommend that you consult with your own lawyer, accountant, or other licensed professional for relevant business decisions. Click here to see our full disclaimer.

In many instances, a business project consumes far more resources than meets the eye. Assume you are running a dog grooming business from the first floor of your two-family house and that your daughter is helping you over the weekends. The business is making $50,000 per year and you want to know whether this represents a positive or negative residual value. In this case, you must deduct from $50,000 all opportunity costs which include the money you would make if you rented the first floor of your house to a business; how much you plus your daughter would earn if you invested the same amount of time and effort into a regular job; and how much the total assets owned by the business would return every year if they were sold off and the cash proceeds were held in a bank account.
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.
Real estate is the obvious choice if you are going to make money on your money. I personally am not at the point where I can do any of this in a meaningful way BUT my parents are and they now own a couple homes outright and are collecting income from them to power their retirement income. It makes a lot more sense for anyone that has a chunk of cash sitting in the bank and are planning on slowly drawing from it because you technically still have all that money in a property (or multiple properties) and can sell them if you really need the lump sum of cash but you’ll earn great interest payments until you do that.
Many people talk about passive income and create the impression that you never have to do anything to keep that income going. The truth is that you will normally have to keep your eye on things if you want it to run smoothly. For example Richard Branson doesn’t run any of the 400+ companies he started but he goes over the numbers each day to make sure they’re performing well and calls the CEO if there are any problems.