MGS declined to abide by the payment terms of their own proposal; requiring me to pay early before completing job. The terms were: "100% upon completion." MGS wrote these terms into its bid. I was rebuilding my house after a fire. I solicited heating/cooling bids from several local contractors. Gary Stevens himself (owner of MGS) plus another MGS employee visited my house to estimate the job. On June 3, 2011 MGS submitted a written bid signed by Mr Stevens. A day or two later I called him to clarify a few items, but I did not ask for or negotiate any changes. He examined a copy of the bid (he told me he was holding it in his hand) and answered my questions. Payment terms were not discussed, as I had no question about them. They were clearly spelled out. On June 8, 2011, I called to accept MGS' bid. Mr Stevens personally came to my house bringing a copy of the bid. We each signed in each other's presence, and we each took copies signed by both of us. Upon completion of about half the work (June 16, 2011) the crew chief (Trent) told me he had been instructed to collect 75% at that time. I showed him the bid, and he acknowledged that I was correct; that I did not owe anything until completion. The next day (June 17, 2011) the office manager (Carol) told me by phone I had to pay 50% before work would be continued. I went to the office and discussed this with Carol on June 21, 2011; she still required 50%. I asked her to have Gary call me. He did not call. On June 27, 2011, I wrote a letter to MGS. I left a few more phone messages, but to no avail. More than 4 months later, on Nov 10, 2011, I gave in and paid $4000 (winter was coming and I wanted heat). The work was quickly completed, and I paid the remainder on completion on Nov 15. MGS proposed the payment terms and wrote them into their bid; I accepted their bid on both price and terms. But after doing half the work they required me to pay early before they would continue. They did not abide by the terms they themselves had proposed and that their owner, Mr Stevens, had personally examined and signed, had presented to me, and that I signed in his presence. To this day, Gary Stevens has not called me back. All work was done properly and professionally, all workmen were friendly and helpful.