Mercedes takes top four spots on Forbes list
                                
                                
                                    (Newser) -
                                    Gas prices may be sinking, but the owners of luxury and high-performance vehicles wouldn't know it. Factoring in $4-plus premium gas, depreciation, insurance, fees, and sales tax, some top cars cost double over a 5-year stretch what owners first paid. Forbes wheels out the  priciest (including 5-year pricetag):