(4) That the county board has attempted to secure as a term of the agreement at least 36 hours prior to the opening of the voting place and at least 36 hours after the close of the voting place, as provided in
G.S.163-166.01, for candidates to place and retrieve political advertising. The agreement may also provide that any political advertising placed outside the times specified in this subsection may be removed by the property owner.
An agreement under this subsection shall be valid for as long as the nonpublic building is used as a voting place.