Writing an e-book is very popular among bloggers, as many have noted that “it's just a bunch of blog posts put together!” You will not only have to make an investment of time and energy to create the e-book, but market it correctly. However, if marketed correctly (through blogging affiliates in your niche, for example), you could have residual sales that last a very long time.
Roofstock – Investing in rental properties is one of those passive income ideas that can be extremely intimidating, especially when it comes to finding tenants. Roofstock lets you buy properties with as little as 20% down that already have tenants living in them. That means you start getting paid from the first day of your investment. You don’t even have to physically visit the properties!
Many bloggers and social media influencers build significant residual income through affiliate partnerships. If a blogger promotes or mentions a product on their site, and readers purchase the product through the link provided, the blogger earns a percentage of the revenue. The same goes for social media influencers. If someone promotes a product on Instagram and their followers purchase it through their link, the Instagrammer would receive a portion of that revenue.
Residual income is calculated as net income less a charge for the cost of capital. The charge is known as the equity charge and is calculated as the value of equity capital multiplied by the cost of equity or the required rate of return on equity. Given the opportunity cost of equity, a company can have positive net income but negative residual income.