Reputation. Look for an established contractor with an extensive customer list.
Warranty. The contractor should be willing and able to offer you a comprehensive written warranty on your project.
Financial stability and strength. A contractor who is financially viable will still be in business during and beyond the warranty period of your project.
Does the contractor have a permanent business location?
How long has the contractor been in business?
Is the contractor a member of a trade association?
Does the contractor have a record of complaints on file with the Office of Consumer Protection?
Will the contractor provide names, addresses and phone numbers of past customers? Call these for references.
Will the contractor allow you to see other projects the company has done, both completed and in progress?
Is the company sufficiently insured?
Will the contractor provide you with a complete and clearly written contract?
Did the contractor submit an unusually low bid compared to others?
Select a contractor on the basis of integrity.
Select a contractor on the basis of competence.
Check the contractor's track record for meeting schedules and deadlines.