Occupancy permits will be issued only when the exterior of the entire townhouse structure is complete, the installation of any curb, all utilities, all functioning water supply and sewage treatment facilities, all necessary storm drainage to insure proper drainage of the lot and surrounding land, rough grading of lots, base course for the driveway and base course for the streets are installed to serve the lot and townhouse dwelling units for which the permit is requested. Streets, if installed prior to final approval, shall not be paved until all heavy construction is completed; shade trees shall not be planted until all grading and earth moving is completed; seeding of grass areas shall be the last operation. The issuance of Certificates of Occupancy will follow the procedures outlined in Section 25-9 of this chapter.