There is an old saying in this business, "A good reputation takes years to build, a bad reputation takes only one job."  
    Researching your prospective contractor is the best way that you can avoid problems with the project at hand. Every reputable contractor will be happy to provide you with a list of past customers which you can use to get an idea of what type of job you can expect to get from them. Use this information and research these references as this is the best source of information you will find as to how well these former customers liked the contractor, and the work that they did. 
    You will want to ask questions about how long their job took to complete. Did the contractor stay on the job till complete or did they move back and forth between jobs? How close to the originally quoted price was the final cost? Were all permits taken care of by the contractor? If problems did occur, how were they handled? How well did their sub-contractors perform their jobs? Was the job site cleaned up daily or was there a mess from start to finish? If it helps, write down anything you think might be helpful to know so that when you do talk to people you will get the answers you need. Happy customers are usually happy to talk about their project and the contractor involved. Similarly, unhappy customers are probably going to be glad to warn others of their experience.
    Sub-contractors play a major role in the success of any job. Many general contractors can do a variety of jobs, but on a larger scale project it is often necessary to bring in sub-contractors. If you have a very good general contractor but he uses less talented subs; electricians, plumbers,masons, etc, then chances are you are not going to be happy with the work. Any major plumbing or electrical work should be performed by licensed contractors only. Most general contractors can change a light switch or install a faucet, however if you want to upgrade to a 200 amp service or connect a new bathroom to the main sewer line, you better have a licensed electrician and plumber to perform that work. Ask your contractor who they plan to use and if they are licensed. If your prospective contractor takes offense to questions like these then you should be wary as to why they are. 
    Check with the Better Business Bureau to see if there have been any claims made against the contractor. 
    Ask family, freinds and neighbors about any experiences that they have had with contractors. This information will be much more useful than just looking in the phone book and hoping that you get lucky.
    Check with your local office of liscense and inspection to see if they have any knowledge of the contractor.
    Basically the more you research your contractor, the better chances are that you will find one that you will be happy with. Your home is one of the biggest investments that you will make. The time you take to check your contractors references should be seen as a way to protect your investment. If you don't like what you hear about them then you should keep looking. Don't allow yourself to be pressured into using someone you are not comfortable with.

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