Md. Code, Tax - Property § 2–213

(a) Each supervisor shall maintain for public inspection, without charge:

(1) a complete set of tax maps for the county together with parcel reference lists; and

(2) on request of an interested party, sales records or transfer voucher forms that relate to sales of real property.

(b) The Department shall provide copies of the information set forth in subsection (a) of this section to the public for a reasonable fee that reflects the cost of reproduction.