Robo-advisors are diversified investment accounts that are automatically managed by a computer algorithm (as opposed to a human money manager). If you want to invest, but don’t have the money, or don’t want to invest with a money manager, robo-advisors are for you! Robo-advisors make investing easier—and cheaper—so they’re perfect for new investors.
Monetize a hobby. While some hobbies actually cost money, others can be transformed into a profitable business venture. Ultimately, it depends on what your hobby is and how talented you are. You could turn your love of photography, for example, into a part-time gig taking family portraits and wedding photos or selling prints on Etsy or at arts fairs.
25. Products – You can create your own product, such as an ebook or computer software. You would then use your blog as a promotion tool to get people to buy your product. As long as you create a legitimate product with a whole lot of value, you should be able to get some buyers, but like everything else with a blog, you’ll need the traffic to get the sells.

ebay is a popular resource for selling various used and unwanted items. However, there are specific sites for selling certain used items such as books, jewelry, wedding dresses, and electronics where you may have greater success. Also, to maximize earnings, it's important to take a great photo of the item and write a compelling, honest description.

Another suggestion for passive income is refinancing your mortgage. Imagine, for example, that you're making monthly mortgage payments of $1,500 now and can reduce that to $1,200 per month by refinancing your home loan at a lower interest rate. That will let you keep $300 in your pocket each month. Of course, refinancing isn't free -- there are closing costs -- and you'll start the clock ticking on a new loan (typically of 15 or 30 years) when you refinance.
Websites like Survey Junkie will pay you a decent chunk of change for the low-maintenance, borderline mindless task of completing surveys. Companies want to understand consumers better, and one way they do that is by compensating survey-takers (a.k.a. you). Most surveys pay between $0.50 and $1.25, and many of them take less than 5 minutes to do. You can read our full Survey Junkie review for more info.