Liquidity is the ease with which you can get your money out of an investment.
Liquidity is defined as the ease of liquefying assets without causing significant impact on its price. Liquid assets are cash, cash equivalents, and other assets that can be easily converted into cash. Sellers and buyers of these assets are abundant.
Buildings and other real estate properties are not liquid assets. This is because it is not easily converted into cash. Prices of these assets may vary depending on the availability of buyers that are interested in said properties.