Maserati Quattroporte is the worst depreciating car with a 64.5% drop in value over five years, losing around $90,000 off its average list price. Porsche 911 is the least depreciating car with only a 9.3% drop in value over five years. Other luxury cars with significant depreciation include Maserati Ghibli, BMW 7 Series, and Jaguar XF.