(c) It shall be the duty of each subcontractor who has furnished, or is furnishing, labor, services, material, fixtures, apparatus or machinery, forms or form work for an existing owner-occupied single family residence, in order to preserve his lien, to notify the occupant either personally or by certified mail, return receipt requested, addressed to the occupant or his agent of the residence within 60 days from his first furnishing labor, services, material, fixtures, apparatus or machinery, forms or form work, that he is supplying labor, services, material, fixtures, apparatus or machinery, forms or form work provided, however, that any notice given after 60 days by the subcontractor shall preserve his lien, but only to the extent that the owner has not been prejudiced by payments made prior to receipt of the notice. The notification shall include a warning to the owner that before any payment is made to the contractor, the owner should receive a waiver of lien executed by each subcontractor who has furnished labor, services, material, fixtures, apparatus or machinery, forms or form work. The notice shall contain the name and address of the subcontractor or material man, the date he started to work or to deliver materials, the type of work done and to be done or the type of materials delivered and to be delivered, and the name of the contractor requesting the work. The notice shall also contain the following warning:
"NOTICE TO OWNER
The subcontractor providing this notice has performed work for or delivered material to your home improvement contractor. These services or materials are being used in the improvements to your residence and entitle the subcontractor to file a lien against your residence if the services or materials are not paid for by your home improvement contractor. A lien waiver will be provided to your contractor when the subcontractor is paid, and you are urged to request this waiver from your contractor when paying for your home improvements."
Such warning shall be in at least 10 point bold face type. For purposes of this Section, notice by certified mail is considered served at the time of its mailing.