Whenever said owners are nonresidents of the Town of West New York, such notice may be given by sending written notice thereof by registered mail to the last known address of the property owner or owners, as shown by the most recent tax lists of the town. Where the owner is a partnership, service upon any partner as above provided shall be sufficient, and where the owners are corporations, service upon any officers, as above provided, shall be sufficient. The appellant shall by affidavit present satisfactory proof to the Board of Adjustment at the time of the hearing that said notices have been duly served as aforesaid. Upon the hearing any party may appear in person, by agent or by attorney.