1) Get good plans!
In this business, I have seen some head scratchers, but the biggest mistake is poor planning. If you don’t have a good set of plans your project will be inefficient and often of poor quality. Your plans should be detailed and include language about the quality of work and materials. If you think good architects are expensive, try good lawyers, without the former you will need the latter.
Sometimes clients think they will save money by camping on the jobsite during a remodel. This is not a cost saver, it’s a recipe for disaster. A job site is often dangerous and often messy. Your contractor should be clean but it still wont be clean enough for healthy living. Not living there allows the workers to get there early, and work longer. This should have a great affect on your timeline, not to mention your sanity.
3) Have a reserve.
Even if you have a good set of plans and a good contract with your contractor, you need to have a reserve when problems or opportunities arise. Existing conditions will not be constant, so expect to have to repair some areas not on the plans. It also lets you look at opportunities as the project is being built so that you can make changes for the better.
4) Call references
Don’t be fooled by a charming contractor with a price that is 30% below the others. He is either leaving something out, or plans to charge you after the project is started. You should ask the references specific questions about the project to make sure the reference is real. If the client has a good relationship with the contractor, they will not mind showing you the completed project. Your inquiry should not be about how much the reference likes the contractor, but rather will their contracting style be a good fit for you.