I had a similar situation with a contractor that put an addition on our house about 14 years ago. He told me the job would take six weeks. I told him that would be fine, I would give him 90 days - to which he replied that would not be necessary that it would only take six weeks. Then I presented him with the contract that called for him to pay me $100 a day for each day from 91 on that the job was not complete.

At day 120 he came to me and said we had to discuss the contract as it was killing him. I told him fine, he had done many extras I had asked for so I told him we would call it even. I then asked him how much longer, he said 10 days. I told him he had two weeks, he told me not to work it would only take 10 days. I told him fine, sign here - where it said he would pay me $200 a day for each day after two weeks. At day 20 he got fired and I finished the little bit that was left and never paid him the balance due.

The moral of the story is take nothing said as binding, get it all in writing.