Maryland Code, Tax-General § 13-520

(1) the record of the proceeding from which the appeal is taken or a certified copy of the record; and

(2) any map, plat, or other document that is connected with the record.

(1) the appearance of a witness to testify; and

(2) the production of any pertinent document.

(1) the sheriff or deputy sheriff of the jurisdiction in which the person subpoenaed is found;

(2) the clerk or a deputy clerk of the Tax Court;

(3) certified mail, return receipt requested; or

(4) a private process server.