even a new car can lose upto 20% of its value the moment it leaves the dealer's lot. no way around it, cars will always depreciate. there are those exceptions like the exotic cars but heck, even if you buy a ferrari you cant expect to sell it at the price you got it unless its one of those collectibles that you keep in the garage for 10+ years before selling.

personally, if you plan to own the car for more than 5 years then depreciation is not a factor anymore. even if you keep the amount you paid for the car in cash, over 5 years you still lose to inflation.