Mich. Comp. Laws § 559.172a

Sec. 72a. If the master deed for a condominium project is recorded after the effective date of this section, a time-share unit shall not be created unless expressly provided for in the condominium documents. If the master deed for a condominium project was recorded on or before the effective date of this section, a time-share unit shall not be created unless the condominium documents are amended to expressly provide for the creation of time-share units. An amendment of the condominium documents to expressly provide for the creation of time-share units is a material alteration of the rights of co-owners and requires the consent of 2/3 of the votes of co-owners and mortgagees as provided in section 90.