Probably the biggest threat to a classical car is rust. Rust will not just lower the value of a classical car, but it will also alter the integrity of the metal. Once rust has started it will continue to grow in size and can possible destroy your car’s entire frame. The ideal thing to do is to keep rust from ever starting. If you have an extremely expensive classical car such as a BMW or a Model T, it is highly suggested that you keep your investment in an environmentally controlled storage facility.