Maryland Code, Commercial Law § 12-620

(a) Notwithstanding the provisions of § 12-601(k) of this subtitle and any provision of an installment sale agreement to the contrary, a buyer may prepay at any time, without penalty, all or any part of the unpaid time balance payable under the installment sale agreement if such agreement is for the retail sale of personal property purchased primarily for personal, family, or household purposes, regardless of the original price of that personal property.