The following steps will help you find the right contractor for the work you need done:

• Get referrals on several contractors by asking friends or family for recommendations. Look at examples of their work to see if it meets your expectations.
• Get rough estimates from all contractors who interest you. It will help you narrow the field of candidates.
• Ask the prospective contractors to email you their sample contract, to make sure you know what terms to expect. 
• Ask the prospective contractors to send you pictures of jobs they have done in the past.
• For a major job, get at least three bids. Give a contractor about three weeks to produce the bid. Read the bids closely; they should detail the materials that will be used. If one contractor is much lower than the others check to make sure he or she is truly capable and experienced.
• When accepting bids, find out how long the contractor has been in business - the longer the better. Ask who finances the contractor's company (usually it's a bank). Ask the bank about the contractor's general solvency. You do not want a contractor to go bankrupt in the middle of your project.
• Determine whether the contractor carries insurance. Every contractor's insurance should cover property damage, liability, and workers' compensation. If the contractor is not covered, you could be liable for hefty fees in case of an accident.