A private act hospital authority, as defined in this part, in addition to the rights and powers granted to such authority by any private act of the general assembly or its charter of incorporation, has as supplemental and additional rights and powers, all powers granted to private act metropolitan hospital authorities in part 5 of this chapter. Any powers granted under this part to a private act hospital authority shall not limit or reduce any power granted to a private act hospital authority by a private act of the general assembly or its charter of incorporation. The rights and powers granted to a private act hospital authority by this part shall not be applicable to any hospital that ceases to be either owned or operated by the governing authority or entity established under the hospital's private act. Nothing in this part shall require a private act hospital authority to bid the purchase or procurement of any goods or services that are not required to be bid by the private act creating such private act hospital authority or its charter of incorporation.