To estimate the price of the 2018 Bentley Continental GT W12 Speed (Top) coupe with 100000 miles and Japanese specs, I started by looking at the new car price for the same model, which is AED 1296500. Given the car is 6 years old, I applied a 10% depreciation per year, resulting in a depreciation factor of 0.531441 (0.9^6). This gives a base depreciated value of approximately AED 688,888. I then considered the listed prices of similar cars: a 2020 Bentley Continental First Edition GT W12 Speed (Top) with 31000 miles listed for AED 879000, and other 2017-2019 models with prices ranging from AED 275000 to AED 790000. Given the high mileage and non-GCC specs of the target car, I adjusted the base value downwards. Factoring in the condition and mileage, I estimated the market price to be around AED 600,000.