In the operation or management of housing projects an authority shall at all times observe the following duties with respect to rentals and tenant selection: (a) it may rent or lease the dwelling accommodations therein only to persons of low income and at rentals within the financial reach of such persons of low income; (b) it may rent or lease to a tenant dwelling accommodations consisting of the number of rooms (but no greater number) which it deems necessary to provide safe and sanitary accommodations to the proposed occupants thereof, without overcrowding; (c) it shall not accept any person as a tenant in any housing project if the person or persons who would occupy the dwelling accommodations have an aggregate annual income in excess of the maximum income limits established by the authority for the purpose of determining what persons or families are of low income; and (d) at least thirty days before establishing or changing the aggregate annual maximum income limits for the purpose of determining what persons or families are persons of low income, an authority shall notify the governing body of the city or county thereof. Nothing contained in this section or § 36-21 shall be construed as limiting the power of an authority to vest in an obligee the right, in the event of a default by the authority, to take possession of a housing project or cause the appointment of a receiver thereof, free from all the restrictions imposed by this section or § 36-21.