A legal maximum on the price at which a good can be sold is called a price

Ceiling

Explanation:

A situation in which the price charged for some marketed objects becomes more or less than the equilibrium price that is determined by market forces of demand and supply, is called Price Ceiling. Government often uses price ceiling to control the maximum selling price of commodities. By doing this, the commodities are made affordable for the public in country. In house rent market, price ceiling is of great importance.