I am a Realtor. My client hired a contractor to do work on the home they are purchasing. The document my client signed says that they are paying the contractor to do XYZ per engineer report for X amount of dollars. The work was not completed and he wants the other half of his money but my client said he is not paying until the work is finished correctly. The contractor said he is going to put a mechanic's lien on the house? Is that possible even though he did not complete what was stated and we have proof of photos?