§ 9. Contents of notice of lien. The notice of lien shall state:

1. The name and residence of the lienor; and if the lienor is a partnership or a corporation, the business address of such firm, or corporation, the names of partners and principal place of business, and if a foreign corporation, its principal place of business within the state.

1-a. The name and address of the lienor's attorney, if any.

2. The name of the owner of the real property against whose interest therein a lien is claimed, and the interest of the owner as far as known to the lienor.

3. The name of the person by whom the lienor was employed, or to whom he furnished or is to furnish materials; or, if the lienor is a contractor or subcontractor, the person with whom the contract was made.

4. The labor performed or materials furnished and the agreed price or value thereof, or materials actually manufactured for but not delivered to the real property and the agreed price or value thereof.

5. The amount unpaid to the lienor for such labor or materials.

6. The time when the first and last items of work were performed and materials were furnished.

7. The property subject to the lien, with a description thereof sufficient for identification; and if in a city or village, its location by street and number, if known; whether the property subject to the lien is (a) real property improved or to be improved with a single family dwelling or (b) not real property improved or to be improved with a single family dwelling. A failure to state the name of the true owner or contractor, or a misdescription of the true owner, shall not affect the validity of the lien. The notice must be verified by the lienor or his agent, to the effect that the statements therein contained are true to his knowledge except as to the matters therein stated to be alleged on information and belief, and that as to those matters he believes it to be true.