Deciding whether to hire a contractor or be your own general contractor is an extremely important decision. Familiarize yourself with the pros and cons of each option before you decide. You may opt for the do-it-yourself route to save money, but don't forget to factor in the value of your time. Hiring a contractor will often get the job done sooner, as many subcontractors give small jobs a lower priority.
The CSLB web site has many helpful tips for working with contractors, including a list of questions to ask before hiring.
Look up a contractor license or Home Improvement Salesperson (HIS) registration to verify information, including complaint disclosure.