“Subdivision” means the division, by any subdivider, of any unit or units of improved or unimproved land, or any portion thereof, shown on the latest equalized county assessment roll as a unit or as contiguous units, for the purpose of sale, lease, or financing, whether immediate or future. Property shall be considered as contiguous units, even if it is separated by roads, streets, utility easement, or railroad rights-of-way. “Subdivision” includes a condominium project, as defined in Section 4125 or 6542 of the Civil Code, a community apartment project, as defined in Section 4105 of the Civil Code, or the conversion of five or more existing dwelling units to a stock cooperative, as defined in of Section 4190 or 6566 of the Civil Code.