Christopher Hill, a friend and quality construction lawyer has posted some interesting articles on Mechanics' Liens. Click here to see his latest: constructionlawva.blogspot.com. While the timing for the filing and releasing of mechanics' liens varies from state to state, Chris includes some great thoughts and comments regarding more generally applicable problems surrounding mechanics' liens. In short, they are tricky animals.
In Iowa and most states, the applicability and proper timing for the filing of mechanics' liens vary between commercial and residential properties. The primary rationale is that in commercial projects the general contractors and owners are more business savvy. Of course, that is not universally the case. Under the current state of economic affairs, mechanics' liens are significant problems for homeowners and commercial owners alike. Pay attention to the specific laws applicable to your situation and don't get caught without someone to help you through the mine field of mechanic liens.