Does the contractor have the proper license? Is his insurance and workman's comp. up to date? To get an answer to those questions you are going to want to ask to see these documents from the contractor.
 Before you decide on whom you are going to hire you are going to want to make some calls. First you are going to want to call the local building department for references. The building inspectors in your area meet with contractors on a weekly or monthly basis and they will be able to give you an idea of who you are dealing with. Another great place to call is the State licensing agencies because they will have a good idea of how the contractors perform compared to their peers as well.
 Will the contractor provide you with references and phone numbers of their most recent clients? Do they have any photos of their most recent projects? If the references are old and the dates of the jobs are far between you want to ask them why that is so. It's usually a sign of bad references which they are trying to avoid telling you about. But sometimes it is for other reasons, such as the business closed due to family emergency or something else.
 How long have they been in business? If you know how long they have been in business you will have a time frame to judge their references by. Another thing that you should do is call the Better Business Bureau to see if they have had any complaints in the past or you can check with the Better Business Bureau online.
 Is their contract simple and straight forward? If the contract is simple and straightforward chances are they are not a very good contractor. The reason for this is that most reliable builders have a large and heavily worded contract. The reason for them having such a large and detailed contract is that the contracts include specifics like materials to be used, warranties, manufacturers and sub-contractors. The more specific the better the builder is likely to be.
 Something else that you are going to want to do is to ask to meet with the job superintendent. The reason for this is that most of the time you are going to be dealing with the superintendent on the job and not the owner of the company so you are going to want to build a good relationship and at least met the person that will be in charge because he will be dealing with the problems of the other employees.
 When will the project begin and what is the realistic finishing time? Many contractors have too many projects under contract and it causes some serious delays in building. If it's going to take a year or more that's probably a sign that the contractor is over worked. A typical home of average size should take roughly 6 months or less to complete. Also if they can't give you a good answer or won't give you an answer the chances are high that they don't really care and might not do that good of a job.