Such agreement between said subdivisions aforesaid may provide for the appointment of a manager or agent of such real property, the application of the rents or income from such real property to the payment of compensation or commission to such manager or agent, to repairs, fire insurance, liability insurance, or such other expense necessary to the maintenance of such real property, as well as the payment of any balance to such political subdivisions in proportion to their interests, or as such agreement may provide, or make any other arrangements in connection with said real property as they deem to be best for their mutual interests: Provided, however, That the provisions of sections 1 and 2 of this act¹ shall not apply to any real property containing minerals and oil beneath or upon the surface thereof.