The governing body of each of the counties in the area of operation of the regional housing authority, the commissioners of the regional housing authority, and the governing body of each such additional county or counties may by resolution declare that there is a need for the inclusion of such county or counties in the area of operation of the regional housing authority, only if:
(1) The governing body of each such additional county or counties finds that insanitary or unsafe inhabited dwelling accommodations exist in such county or there is a shortage of safe or sanitary dwelling accommodations in such county available to persons of low income at rentals they can afford; and(2) The governing body of each of the counties then included in the area of operation of the regional housing authority, the commissioners of the regional housing authority, and the governing body of each such additional county or counties find that the regional housing authority would be a more efficient or economical administrative unit if the area of operation of the regional housing authority is increased to include such additional county or counties.