No person, while engaged in any profit or nonprofit solicitation, shall knock at the door or ring the bell of any home, apartment, apartment building or other dwelling unit in the Municipality upon which is displayed at the entrance a notice which reads "No Peddlers or Solicitors Allowed, " or which otherwise clearly purports to prohibit peddlers or solicitors on the premises, unless such peddler or solicitor is, or has been invited upon the premises by the owner, lessee or occupant thereof.