If the amount due for such cleaning, laundering, repairing, dyeing or pressing is not paid within six months after it is due, the property subject to such lien, or so much thereof as is necessary to satisfy such lien, may be sold by the person, firm, association or corporation holding such lien at public or private sale for cash, and the proceeds of such sale, after payment of the expenses thereof, shall be applied upon the indebtedness, and any remainder shall be paid to the owner of such property. Before making such sale the person, firm or corporation holding such lien shall give thirty days’ written notice thereof by registered or certified mail sent to the last-known post-office address of such owner, and, in addition thereto, shall advertise the time and place thereof three times in a newspaper having a circulation in the community.