Except as otherwise provided in this section, each condominium unit constitutes a separate parcel of real estate. If there is any unit owner other than the declarant, each unit, together with its common element interest, but excluding its common element interest in convertible land and in any withdrawable land within which the declarant has the right to create units or limited common elements, shall be separately assessed and taxed. Each convertible land and withdrawable land within which the declarant has the right to create units or limited common elements shall be separately assessed and taxed against the declarant.