(1) No mortgage may be recorded in any of the counties comprising the Metropolitan Commuter Transportation District or in Erie County unless a statement is included in the mortgage or in a separate statement attached thereto, stating whether the mortgage is a mortgage of real property principally improved by a structure containing in the aggregate not more than six residential dwelling units, each unit containing separate cooking facilities. Where the real property covered by such mortgage contains or will contain other improvements, the determination of the nature of the principal improvement will be made in accordance with section 642.3(c)(1)(i) of this Title.

(2) A statement in the mortgage that the real property is principally improved or is to be principally improved by a one- or two-family residence or dwelling, sufficient to claim the $10,000 deduction from the additional tax, as provided in section 642.2(b)(2) of this Title, is sufficient to satisfy the statement requirements of this section.