In this section the following words have the meanings indicated. “Nonresident firm” means a business entity that: has one office that: is a principal office for the entity; and is not located in the State; or for an entity that has offices in multiple states, has not had a principal office located in the State for at least 6 months immediately before the date of a request for proposals. “Preference” includes: a percentage preference; an employee residency requirement; or any other provision that favors an offeror from one state to the disadvantage of an offeror from another state. “Principal office” means a primary place of business that is staffed on a regular basis to provide the services that are requested by a unit in a request for proposals. “Principal office” does not include a satellite office or an office that is minimally staffed and is not open on a regular basis to provide the services that are requested by a unit in a request for proposals. “Request for proposals” means a request for architectural services or engineering services that is issued in accordance with § 13–112 of this article. “Resident firm” means a business entity that: is licensed or otherwise authorized to provide architectural or engineering services in the State; and for an entity that has one office, the office is located in the State; or for an entity that has offices in multiple states, has had a principal office located in the State for at least 6 months immediately before the date of a request for proposals. “Resident firm” includes a joint venture that: was entered into before the date of the request for proposals for which the joint venture submits a proposal; and includes one party that: holds at least a 51% interest in the joint venture; and meets the requirements under subparagraph (i) of this paragraph. Subject to subsection (d) of this section, a unit shall apply a preference to a proposal from a resident firm if: a nonresident firm is: a responsible offeror; and determined to be the most qualified person to submit a proposal in accordance with § 13–112 of this article; and the state in which the principal office of the nonresident firm is located has a preference that favors an offeror from that state to the disadvantage of an offeror from this State; a resident firm: is a responsible offeror; and at the same time that it submits the proposal for which the preference would apply, certifies that it meets the requirements for a resident firm; and the preference: is the same as the preference referenced in item (1)(ii) of this subsection; and does not conflict with a federal law or grant affecting the procurement contract. At the request of a unit, a nonresident firm shall provide the following documentation for the state in which the principal office of the nonresident firm is located: a copy of the current statute, resolution, policy, procedure, or executive order that establishes a preference that favors an offeror from that state to the disadvantage of an offeror from this State; or a certification that the other state does not have a preference that favors an offeror from that state to the disadvantage of an offeror from this State. If a resident firm qualifies for a preference established under this section and for another preference established under this Division II, the unit: may not apply more than one preference to the proposal from the resident firm; and shall apply the preference to the proposal from the resident firm that is most advantageous to the resident firm. If, when making a determination of qualification under § 13–112 of this article, a unit determines that a proposal from a resident firm and a proposal from a nonresident firm are equally qualified, the unit may apply a preference to the proposal from the resident firm. A unit may not apply a preference to a proposal submitted by a resident firm if the resident firm does not submit the certification required under subsection (b)(2)(ii) of this section at the same time that it submits the proposal. The Board shall: post and maintain a list of all states with a preference that favors an offeror from that state to the disadvantage of an offeror from this State; and adopt regulations to implement this section.