Just finished (I hope) the worst remodel I have ever been involved with today (9 months long). I have learned that people who can afford to do a massive remodel are usually the loopiest. The total job ran $400K and our part was about $18K on a 3000 sqft home. We did the addition at standard pricing but the remodel part was T&M. If you are trying to give a guestimate triple your time and money and keep in mind that youll have ten times the trips to that job. I turn down remodels every week because it really slows down the other new construction jobs.