Insurance Co. says car must be in a locked garage

Here in CT. If a car is over 20 years old it can get collector car plates. Over 25 they are antique plates. Both take car off normal property tax rolls and drop value to $500 which means about $15 dollars a year on property taxes vs. a couple of hundred. (Yes CT is tax haven) ...

I think you mean "tax hell" not "tax haven". Definition of HAVEN