Notwithstanding § 5-128(b) of this subtitle, a person may purchase more than one regulated firearm in a 30-day period if: the person applies for and the Secretary approves a multiple purchase; and the purchase of the regulated firearms is for a private collection or a collector series; the purchase of the regulated firearms is a bulk purchase from an estate sale; the purchase of not more than two regulated firearms is a multiple purchase to take advantage of a licensee’s discounted price available only for a multiple purchase; and the purchaser is prohibited from purchasing a regulated firearm during the following 30-day period unless approved under item (i) or (ii) of this item; or the purchase is for other purposes similar to items (i) through (iii) of this item. The application for a multiple purchase shall: list the regulated firearms to be purchased; state the purpose of the purchase of more than one regulated firearm in a 30-day period; be witnessed by a licensee or designated law enforcement agency; and be signed under the penalty of perjury by the firearm applicant. The application for a multiple purchase of regulated firearms shall be attached to a completed firearm application and forwarded to the Secretary by a licensee or designated law enforcement agency. On receipt of the firearm application and the application for a multiple purchase, the Secretary shall conduct a background investigation as required in § 5-121 of this subtitle. A person who violates this section is guilty of a misdemeanor and on conviction is subject to imprisonment not exceeding 3 years or a fine not exceeding $5,000 or both.