Subject to the provisions of the declaration and other provisions of law, a unit owner (1) may make an improvement or alteration to the unit that does not impair the structural integrity or mechanical systems or lessen the support of a portion of the common interest community; (2) may not change the appearance of the common elements or the exterior appearance of a unit or any portion of the common interest community without permission of the association; (3) after acquiring an adjoining unit or an adjoining part of an adjoining unit, may remove or alter an intervening partition or create apertures in the partition even if the partition in whole or in part is a common element, if the removal or alteration does not impair the structural integrity or mechanical systems or lessen the support of a portion of the common interest community and is completed according to applicable codes and in a skillful and workmanlike manner. Removal of partitions or creation of apertures under this paragraph is not an alteration of boundaries.