A friend convinced the owner of a vacant store to allow him use of the store for a one-year period for $12,000, to be payable in monthly installments of $1,000. This amount was significantly below its fair rental value. Their agreement was not reduced to writing. Near the end of the year, the friend and the owner discussed an extension of the arrangement, but did not arrive at an agreement. The owner informed the friend that, if the friend remained, the rent would be raised to its market value. The friend objected. After the end of the one-year period, the friend remained in the store. The friend sent the owner a $1,000 rent check. The owner returned it to the friend, indicating that the rent was now the fair rental value of the premises. Is the owner correct that the friend is obligated to pay the fair rental value of the premises?