>"Two years ago he paid about $160,000 to insure $20 million worth of Cadillacs and Volvos on his lot, where about a third of the inventory is kept outside. This year he’s paying almost $600,000."

Surely a dealer could install some hail-proof canopies for a lot less than $600,000?

Something like this perhaps? http://www.wssl.com/Car_Lot_Canopy.html