This is the first and last comment I will make on the subject, but be careful when telling someone to withold money from a contractor--depending on the laws in various states, the contractor may be able to go down to the courthouse and simply enter a lien on his home for witholding payment, thus clouding the title to the property and possibly harming his credit or ability to sell or re-finance.

Thorsen, check out contractors/mechanic's liens in your state and good luck.