http://www.smithlandmeier.com/mechlien.htm
STEPS REQUIRED OF A GENERAL CONTRACTOR TO ESTABLISH A MECHANIC'S LIEN
The requirements that must be met by a general contractor to establish a mechanic's lien are as follows:
A valid contract: There must be a valid contractor for performance of the work. Although the contract can be verbal, it is always better practice to have a written contract, with a complete list of all work to be performed, and all of the terms of the contract clearly stated.
The contract must be with the owner, or with someone "knowingly permitted" by the owner: The contractor should determine at the outset whether the person engaging his services is the owner of the real estate, or is knowingly permitted by the owner to make improvements. The best practice is to determine (by a current title commitment or title search) the identity of the owner of the real estate, and require the owner to join in the construction contract. ....
Married Persons: Where one spouse (i.e., the wife) holds title to the property, and the other spouse (i.e., the husband) enters into the construction contract, the contractor claiming a mechanic's lien would have to prove that the spouse holding title knowingly permitted the other spouse to make the improvements. It is therefore best to require both spouses to sign the contract.
The contractor must furnish materials or services: The types of "materials or services" which must be furnished to create a contractor's lien are specifically described in the mechanic's lien statute. The statute is very detailed, and almost all types of materials or services used in construction are included.
Performance of the contract: The contractor must complete work under the contract, or show a valid excuse for non-performance.
Sworn Contractor's Affidavit: The contractor is not entitled to be paid unless and until he gives the owner a sworn contractor's statement, and a Notice about subcontractors. Therefore, this step is crucial to both your right to be paid, and your right to claim a mechanic's lien.