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:
(1) It may rent or lease the dwelling accommodations in the projects only to persons of low income or to persons of moderate to low income and at rentals within the financial reach of such persons;
(2) It may rent or lease to a tenant dwelling accommodations consisting of the number of rooms, but no greater number, which it considers necessary to provide safe and sanitary accommodations to the proposed occupants of the accommodations, without overcrowding.