Mont. Code Ann. § 70-23-802

Ninety percent of the unit owners may agree that the property is obsolete in whole or in part and whether or not it shall be renewed and restored or sold and the proceeds of sale distributed. If 90% of the unit owners agree to renew and restore the property, the expense thereof shall be paid by all the unit owners as common expenses. If 90% of the unit owners agree to sell the property, the property shall be considered removed from the provisions of this chapter.