In addition to the powers conferred upon a city by other provisions of the Greater Municipality Parking Law, a city is empowered to borrow money or accept contributions, grants or other financial assistance from the federal government for, or in aid of, any parking facility project within its area of operation; and to these ends, to comply with the conditions, trust indentures, leases or agreements as may be necessary, convenient or desirable. It is the purpose and intent of the Greater Municipality Parking Law to authorize every city to do any and all things necessary, convenient or desirable to secure the financial aid or cooperation of the federal government in the undertaking, acquisition, construction, maintenance or operation of any parking facility project of the city.