A Mechanic's Lien is a claim placed when a architect, surveyor or an enigineer who has done work but was not paid in full. Mechanics liens are prevent the property owner from selling until the debt is paid in full.

There are attornies who can help you file a lien. This is helpful because of the varying Mechanic's Lien laws in different states. There is also software that will enable you to set up a lien yourself.