What are "investment properties" primarily used for?

Investment properties are primarily used to generate profit through rental or resale. This definition encapsulates the fundamental purpose of such properties, which is to serve as a source of income for investors. Rental properties can provide a steady stream of cash flow, while properties that are bought with the intention of resale can appreciate in value, allowing investors to sell them for a profit.

In contrast, other options focus on personal or recreational use rather than profit-making. For example, residing in a property for personal use indicates that the primary intention is housing rather than investment. Serving as vacation retreats also aligns more with personal enjoyment and less with generating income. Increasing local tax revenue does contribute to community finances but is not a primary purpose for holding investment properties themselves. Hence, option B uniquely identifies the core focus of investment properties as a means to create financial gain.