Rock rent.

• rack-rent: an exorbitant rent
• rack-rent: the full rent of a property, including both land and improvements if it were subject to an immediate open-market rental review
• Castle Rackrent: a short novel by Maria Edgeworth published in 1800, is often regarded as the first historical novel, the first regional novel in English, the first Anglo-Irish novel, the first Big House novel and the first saga novel