As such, underwriters pay a lot of attention to where the cars they will be insuring are garaged. “Policyholders with large, important collections will have storage facilities custom built for this purpose with temperature and humidity controls, special light filters, monitored fire alarms, cameras and motion sensors,” says Standring.

Chubb has a client in Florida—with a collection worth in excess of $100 million—whose facility is designed so cars can be moved up to the second floor in the event of a flood. The insurer will also do thermal-scan inspections of a storage spot. At least once, this service turned up a hot spot on the main circuit-breaker panel that could only be seen in an infrared view—a problem that could have resulted in a fire-causing short.

Even for much less-exalted collections, most insurers will require vehicles to be kept in a garage—though some policies will make exceptions for carports in Sun Belt areas where garages are rare. 

Another common cause of non-driving claims: damages that result from flying rocks when a car is being transported—to a show or a second home. When sending a car overseas, insurers generally prefer it be done by air freight rather than a cargo ship. And for domestic transportation, the ideal is a fully enclosed transport vehicle, not an open-bed truck, says Donald Soss, a vice president in Fireman's Fund Private Wealth group.

When actual driving incidents occur, a disproportionate share happens in the spring, right after a car is first removed from its winter hibernation and is at its most temperamental. “On that first ride of the spring, you hit the pedal and it goes straight to the floor,” says Hagerty, describing a not-uncommon cause of claims.

As with so many other lines of business, one way carriers and specialists look to separate themselves from the competition is with the quality of their claims service—an especially important point for classic-car collectors.

Given the age and rarity of the assets, finding spare parts can be both difficult and expensive. So when shopping for a carrier for a client—who is more likely to view his car as a favorite pet than four wheels and an engine—independent agents and brokers should be sure to choose a partner that can draw on vast experience (and robust databases) to help locate, for example, the right fender.

“When a customer calls us with a claim, it takes seconds to put them at ease—because they immediately understand we know what we're talking about,” says Drewry. A standard-lines carrier “might be good with a Toyota Camry—but  we know what it takes to repair a Chevelle LS6.”

Another important consideration: Does the policy allow for insureds to use their own, preferred restoration shop? Many do (and underwriters maintain lists of shops they can recommend).

“We had a client in Florida who wanted to work with a specialist repair shop in Wisconsin—and we had no qualms with that,” says Jim Fiske, vice president and U.S. marketing manager for Chubb Personal Insurance.

While all the carriers and specialists interviewed by NU stressed they will let clients use the repair shops they are most comfortable with, Hagerty has a unique twist: The company will pay their insureds an hourly wage if they do the repairs themselves.