To estimate the price of the 2021 Isuzu D-Max GT I4 3.0L Turbocharged (Diesel) GT Diesel (Top+), I first looked at the selling price of a 2020 Isuzu D-Max I4 1.9L (Diesel) with 246000 km mileage, which sold for SAR 55700 on 2024-01-31. Given the higher engine size and newer model year of the target car, it should be valued higher. Next, I considered the listed prices of similar cars. The closest match is a 2021 Isuzu D-Max GT I4 3.0L Turbocharged (Diesel) with 108000 km listed for SAR 82500. Another similar car, a 2021 Isuzu D-Max I4 3.0L Turbocharged (Diesel) with 109000 km, is listed for SAR 95000. Considering these listings, the average listed price is around SAR 88750. However, listed prices are generally higher than selling prices. Factoring in the average condition of the target car, I adjusted the estimate downwards. Additionally, I considered the depreciation rate of 10% per year for a 2021 model, which would be around 30% depreciation from the new car price. Combining all these factors, I arrived at the final estimate.