It shall be the duty of the city council to furnish the city secretary with a written order to place a building structure on the agenda as promptly after the preparation thereof as is practicable. The failure to so furnish a copy or written notice thereof, however, shall not have the effect of validating any building permit, removal permit or demolition permit issued in ignorance of any written order or agenda. In any instance in which any permit may not be required, it shall be the duty of the city council to give notice of any written order or the agenda or the preservation plan or amendment thereof to the owner or owners of any property included within the scope thereof, which notice shall be deemed complete when actually given, orally or in writing, to the owner or owners, or when written notice thereof is deposited in the United States mail, postage prepaid, certified, with return receipt requested, addressed to the owner or owners, whichever event first occurs. No person or entity to whom any permit is issued or who, if no permit is required, commences to construct, reconstruct, alter, change, restore, remove or demolish any exterior architectural feature of any building or structure without actual or constructive notice of any written order of the agenda or preservation plan or amendment thereof, as the case may be, as required by the provisions of this section, may be found guilty of a misdemeanor as in this article provided. Each person or entity shall be amenable to the civil sanctions provided in this article.