Many people invest in rental properties simply because of the cash flow, the extra money that is left after all the bills have been paid. Real estate is secured by a physical asset and is an overwhelmingly stable investment. In the vast majority of cases, an investment property will retain its value and appreciate over time. A real estate entrepreneur or a real estate investor like southern indiana real estate is someone who actively or passively invests in real estate. An active investor may buy a property, make repairs or improvements to the property, and sell it later for a profit.