Mont. Code Ann. § 71-3-1401

Hotelkeepers and boardinghouse and lodginghouse keepers have a lien upon the baggage and other property of value brought into the hotel, inn, boardinghouse, or lodginghouse by a guest, boarder, or lodger for the guest's, boarder's, or lodger's accommodation, board, or lodging and room rent and extras that are furnished at the guest's, boarder's, or lodger's request, with the right of the possession of the baggage or other property of value until all charges are paid. This section may not be construed to give a lien upon property sold on the installment plan, title to which is to remain in the vendor until final payment.