The authority is authorized to fix rentals and other charges which any user shall pay to the authority for the use of the project or part thereof or combination thereof, and to charge and collect the same, and to lease and make contracts with political subdivisions and agencies with respect to use of any part of the project. The rentals and other charges shall be so fixed and adjusted in respect to the aggregate thereof from the project or any part thereof so as to provide a fund sufficient with other revenues of such project, if any, to pay the cost of maintaining, repairing, and operating the project, including the reserves for extraordinary repairs and insurance, unless such cost shall be otherwise provided for, which cost shall be deemed to include the expenses incurred by the authority on account of the project for water, light, sewer, and other services furnished by other facilities at the project.