Mont. Code Ann. § 15-17-319

A municipality may sell, donate, or lease property it acquires under 15-17-317 in the same manner as a county may sell, donate, or lease tax-deed property under Title 7, chapter 8, part 23. All money received by the municipality from the sale or lease of the land, after payment of the cost of sale, not to exceed $25, must be paid into the improvement fund to the extent of the delinquent assessments, interest, and penalties. The surplus, if any, must be paid into any revolving fund that secures payment of special assessments or, if there are none, to the general fund of the municipality.