Industrial office parks shall be a minimum of 25 acres in land area and they shall have no less than 500 feet of frontage on a public road. The Planning Board shall require the applicant to establish such organizational, administrative and financial arrangements and guarantees as are necessary to satisfy the board that common property can be adequately maintained on a permanent basis. Lot sizes and dimensions shall be freely disposed throughout the industrial office park provided the development in total does not exceed the height, floor area ratio or coverage requirements of this district. Yards, lot areas and other dimensional requirements of this chapter may be altered in the internal parts of the industrial office park provided the external landscape buffers and setbacks are maintained.