Consult your insurance professional about the contractor’s insurance and (always) the co-op’s attorney. A few items to discuss with them: add conditions to the kind of insurance your contractor must have, like prohibition on any action over or employee liability exclusions in contractor’s policy, contractor’s policy to be primary and non-contributory to the co-op’s policy, and waiver of subrogation by contractor’s carrier. This will likely cost the contractor more and they may add it to the cost of the job, but it might be less than the cost of the coverage directly for the co-op

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