The public housing maintenance fund of commercial housing is generally paid in one lump sum. If the fund is not enough in the later period of housing use, the owners who have owners and account for more than two-thirds of the total number can pay the second housing maintenance fund through discussion. It is mainly used for major and medium-sized repairs and renovation projects of main structures, public parts and public facilities and equipment after the warranty period expires. Generally calculated according to the construction area of the purchased house. The amount of the first residential special maintenance fund deposited per square meter of construction area is 5% to 8% of the local residential construction and installation project cost per square meter.