An assessor is a person whose job involves determining how much a house or building is worth. After an assessor establishes the value of a property, it can be taxed appropriately.
An assessor, sometimes called a "tax assessor," works for a city or county, aiding the process of collecting taxes from people who own property there. In order to figure out how much someone owes, an assessor compares the person's house to the others in the neighborhood and tallies up things like square footage, number of rooms, and acres of land. In Latin an assessor is "an assistant," though in Late Latin it means "one who assesses taxes."