Landlord not to claim or receive anything in excess of fair rent

(1) Where the Rent Control Court has determined the fair rent of a building (a) the landlord shall not claim, receive or stipulate for the payment of (i) any premium or other like sum in addition to such fair rent, or (ii) save as provided in section 6, or section 7 anything in excess of such fair rent: Provided that the landlord may receive, or stipulate for the payment of an amount not exceeding one month's rent by way of advance: save as provided in clause (a), any sum or any rent paid in addition to, or in excess of such fair rent, whether before or after the commencement of this Act, in consideration of the grant, continuance or renewal of the tenancy of the building after such commencement, shall be refunded by the landlord to the person by whom it was paid or, at the option of such person, shall be otherwise adjusted by the landlord: Provided that where before the determination of the fair rent, rent has been paid in excess thereof, the refund or adjustment shall be limited to the amount paid in excess for a period of three years immediately before the institution of any proceedings for such determination. (2) Any stipulation in contravention of sub-section (1) shall be null and void.