My fence contractor will not provide proof of insurance or workman's comp. He has not finished the job and we will not pay without it being done completely and him showing the requested documents OR signing of a lien waiver. There is no signed contract and the first written quote he gave didn't even have his information on it. He recently bought the business and is using the previous owners forms. He finally got us a new quote on paperwork that had removed the previous owner, but he changed all the prices! He is threatening to place a lien on my house. Any advice?