Interest income

There are three types of income—earned, portfolio and passive income. Most types of passive income are derived from rental/property, while other types of passive income are derived from royalties from patents or license agreements. An income stream falling into this category is one where money is received usually on a regular basis, without continuing effort. This does not mean no effort at all; most passive income streams require great effort to start with.Passive Activity Income- is defined to include all income generated from rental real estate investments-- regardless of how active the investor is in managing the property or properties.(Real Estate Principles A Value Approach 2nd edition pg.519)
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