Your 'comprehensive' coverage will cover the trailer only if your declarations page lists it as covered, or if you acquired it during the policy period and reported it to your insurance company within thirty days of its purchase. I do not believe the car on the trailer nor the few expensive pieces of equipment that were on the trailer will be covered. Depending on what exactly were the few expensive pieces of equipment, your homeowner's insurance policy or renter's insurance policy may be able to offer some coverage.
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