The state Division of Consumer Affairs announced the results of its operation Wednesday.
Investigators posing as homeowners responded to home repair advertisements after the August storm, inviting contractors to give repair estimates.
Twelve of the 16 contractors who came to the house in the Bergen County town of Lyndhurst to provide estimates were unregistered with the state.
Eight of the contractors had no business information on file. Four others had filed business records with the state but had not registered.
Consumer Affairs Director Tom Calcagni says complaints about home improvement contractors are common, representing 1,400 of 13,800 complaints filed with the division in 2010.
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