In the discretion of the Authority any bonds issued under the provisions of this chapter may be secured by a trust agreement between the Authority and a corporate trustee, which may be any trust company or bank having the powers of a trust company. The trust agreement or the resolution providing for the issuance of bonds may pledge or assign the revenues to be received and provide for the mortgage of any project or property or any part thereof. However, the Authority shall have no power to encumber its real property or create any estate or interest therein other than encumbrances on structures not extending to the real property upon which such structures are located. The trust agreement or resolution may contain reasonable, proper and lawful provisions for protecting and enforcing the rights and remedies of the bondholders. The trust agreement or resolution may include covenants setting forth the duties of the Authority in relation to the acquisition of property and the planning, development, acquisition, construction, rehabilitation, establishment, improvement, extension, enlargement, maintenance, repair, operation and insurance of the project in connection with which such bonds have been authorized, the rates and fees to be charged, the custody, safeguarding and application of all moneys, and conditions or limitations with respect to the issuance of additional bonds. It shall be lawful for any bank or trust company incorporated under the laws of the Commonwealth which may act as depository of the proceeds of bonds or of revenue, to furnish such indemnifying bonds or to pledge such securities as may be required by the Authority. The trust agreement may set forth the rights of action by bondholders and other provisions the Authority deems reasonable and proper for the security of the bondholders. All expenses incurred in carrying out the provisions of the trust agreement or resolution may be treated as a part of the operation of the project.