Horror stories about conflicts between homeowners and home-improvement contractors abound, but there are ways to prevent or minimize problems. Richard L. Pierce, a Redwood City attorney who specializes in home-improvement issues, told homeowners how to protect themselves during a recent talk sponsored by the San Mateo County Law Library in Redwood City. Contractors are regulated by the Contractors State License Board, whose primary goal is to protect the public. The board enforces its rules strictly and can be "real harsh, very harsh" when the rules aren't followed, Pierce said. Unlicensed contractors who get into disputes can be required to refund the money they were paid for a project, Pierce said. They can also be arrested. Structural work -- including repairs, alterations, additions, replacements and improvements -- costing more than $500 must be performed by a state-licensed contractor.