Office properties are used for professional or business offices. These can be categorized into three sub-types: Class A (high-end, “trophy” buildings with the best amenities and infrastructure), Class B (average or above-average buildings without the special features of Class A), and Class C (older buildings needing maintenance and located in less desirable areas). Office buildings can be single-tenanted or multi-tenanted, and they can range from small professional buildings to towering skyscrapers.