I’m a 45 year old business owner who also has focussed on diversifying my income streams. I have a short term vacation rental in Florida that I bought for $390k in 2012 and net rental income for the last three years has been growing steadily. 2015 I am at $70k gross right now but should end up at $80-85k with net around $45k plus we use the place about 35 nights a year.
You don't have to be Paul McCartney to rack up residuals. You might own properties that you rent out even though you're not a Realtor. Maybe a blog you started took off, and while you no longer work there, you still collect part of the profits. Or perhaps you're a serial entrepreneur who creates companies and moves on. You, too, are earning residual income.

Successful YouTubers choose a theme for their channel—ranging from humorous commentary to gardening. As you acquire subscribers to your channel, your number of views becomes more consistent, which in turn grows your residual income. While you’ll need to produce regular videos to maintain your following, a couple hours of filming and editing pales in comparison to the revenue you can generate with minimum effort.
Lending Club went public in 2014 and is now worth about $1.7B. They advertise P2P lending returns of over 7% for well-diversified portfolios of over 100 notes. I’ve personally been able to achieve a 7.4% annual return over the past two years in a completely passive way by investing in A and AA notes. Others have achieved a 10% annual return through relatively minimum effort.
The second form of residual income, passive income, is often a vital part of wealth creation. There are only so many hours in each day, and when a person trades hours for dollars, there is a maximum amount of income that person can earn. For instance, if a person earns a specific amount each hour, there is a limit to how many hours are available to work. Once they reach that maximum amount of time, they cannot earn more money.
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.