The property of an authority is declared to be public property used for essential public purposes, and such property and an authority shall be exempt from all taxes and assessments of the city, the county, the State or any political subdivision thereof. In lieu of such taxes an authority may agree to make annual payments to such city or county for improvements, services and facilities furnished by such city or county for the benefit of the housing project, in amounts not to exceed the regular taxes which would be levied on such projects by the aforesaid taxing bodies if the project were not exempt therefrom. Bonds and other obligations of an authority are declared to be issued for an essential public and governmental purpose and to be public instrumentalities, and together with interest thereon and income therefrom, shall be exempt from taxes.