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.

After these tenants move out, I'm thinking of just keeping the rental empty with furniture. It sounds stupid to give up $4,200 a month, but I really hate dealing with the homeowner association, move-in/move-out rules, and maintenance issues. Given that the condo doesn't have a mortgage and I have to pay taxes on some of the rental income, I'm not giving up that much. The condo can be a place for my sister, parents, or in-laws to crash when they want to stay in SF for longer than a week or two.

For most of us, if you want to increase your income, you usually have to put in more time. Either that, or find a job that will pay you more per hour or for the physicians out there, do what reimburses you the best. We spend tons of time trying to figure out how to gain a promotion, find another job that will pay us more, or rearrange our schedules so we can get some overtime.
Managerial accounting defines residual income in a corporate setting as the amount of leftover operating profit after all costs of capital used to generate the revenues have been paid. It is also considered the company's net operating income or the amount of profit that exceed its required rate of return. Residual income is normally used to assess the performance of a capital investment, team, department or business unit.