After preliminary approval of the entire planned development is given, a final plan of a portion within the planned development may be approved if:
(a) The portion is more than two (2) acres in size.
(b) The plan of the portion meets all requirements of a final plan.
(c) The dwelling unit density within the portion does not exceed the dwelling unit density allowable for the least restrictive use for that area under existing zoning.
(d) The portion can function as an independent development unit with adequate access, services, utilities, open space, etc.
(e) The developer subdivides and improves all public rights-of-way necessary to support the portion.
(f) The remaining portion is not left as an undevelopable remnant.