Md. Code, Bus. Reg. § 12-102

(a) This title does not apply to a transaction that involves: (1) merchandise acquired from an established manufacturer or dealer who holds a license under this title, other than a pawnbroker, if the dealer who acquires the merchandise keeps an invoice or other customary proof of origin for the merchandise; (2) a metal acquired for use in dentistry by a dentist licensed to practice dentistry under Title 4 of the Health Occupations Article; (3) coins; or (4) the purchase of junk or scrap metal that is subject to the record keeping and reporting requirements under § 17–1011 of this article. (b) If a retail jeweler has a fixed business address in the State, this title does not apply to a transaction in which the retail jeweler: (1) accepts, in accordance with a posted return policy, the return of an item that the jeweler originally sold; (2) accepts, in accordance with a published trade–in policy, merchandise in trade that the jeweler originally sold; (3) repossesses merchandise that the jeweler originally sold, if the original buyer has defaulted; (4) retains merchandise that the jeweler originally accepted for repair as a bailee for hire, if the customer who deposited the merchandise: (i) defaulted; or (ii) failed to reclaim the merchandise within the time agreed on with the jeweler; (5) accumulates pieces of precious metals in the course of performing repairs, remountings, fabrications, or custom orders; or (6) participates in a remount sale. (c) Except as otherwise provided in this title, this title does not apply to a pawnbroker located in a county that regulates pawnbrokers unless the pawnbroker does business as a dealer. (d) (1) A county or municipal corporation may not enact a law to regulate dealers or coins. (2) This title supersedes any existing law of a county or municipal corporation that regulates dealers or coins.