Which of the following is NOT one of the four forces that affect property value?

The four primary forces that affect property value include physical (environmental), economic, social, and political factors. Each of these forces plays a significant role in determining the market value and desirability of real property.

The physical (environmental) force refers to the tangible aspects of property such as location, land use, and zoning regulations. These can directly impact a property's functionality and attractiveness.

The economic force incorporates broader market trends and conditions, including interest rates, employment rates, and overall economic health. These factors can influence buyer behavior and property demand.

Social forces encompass demographics, lifestyle preferences, and community trends. These can shift property demand based on what potential buyers are looking for in a neighborhood.

The psychological force, while relevant in some aspects of real estate, is not formally categorized in the standard framework that appraisers use. Psychological factors can influence buyer perceptions and emotions, but they are not one of the established four forces that directly impact property value in a systematic way. Hence, identifying it as not one of the four main forces is correct.