The effectuation of the authorized purposes of the authorities created under this chapter shall and will be in all respects for the benefit of the residents of incorporated cities for the increase of their commerce and prosperity, since such authorities will be performing essential governmental functions, and for the improvement of their health, safety and living conditions, and, in effectuating such purposes, such authorities shall not be required to pay any taxes or assessments upon any property acquired or used by them for such purposes. In lieu of such taxes or special assessments an authority may agree to make payments to the city or the county or any political subdivision. The bonds issued by any authority, their transfer and the income therefrom, including any profits made on the sale thereof, shall at all times be free from taxation within this State.