Contract signed May 2007, work began June 2007 to be completed within 10 weeks. No sign of contractor since late September. Job is 90% done, but not complete. Contractor has not been by for final payment, nor has he called with for any other reason. We recieved a call from a lumber vendor saying they were placing a mechanics lien on our house for non-payment from contractor. When is a job considered abandoned? And are we liable for final payment under circumstances?