You Must, Must, Must, Must Check References and Trust Your Gut.
Go see the actual homes of your contractor’s previous clients if they will permit you to do so. Many homeowners are happy to show off their new homes if they are happy with the work. Trust your gut. How responsive are they with your questions and requests? Do you LIKE them? Sometimes this last one is the most important. They will be part of your life for many months, if not years, so take the time to do your homework properly.
There is more in my book Dear Homeowner, Please Take My Advice. Sincerely, An Architect pertaining to selecting a contractor... Along with a myriad of other wonderful bits of information to help you properly prepare for your home building project!