To estimate the price of the 2021 BMW 420 Agency Warranty M Kit coupe with 90000 km mileage, I considered the listed prices of similar cars. The closest matches are two 2021 BMW 420 M Kit coupes with mileages of 83000 km and 80000 km, both listed for AED 169750. Given the similar specifications and slightly lower mileage, these listings provide a strong reference point. Additionally, I reviewed other listings of 2019 and 2022 models with varying mileages and conditions, noting that 2019 models with higher mileages are listed between AED 75000 and AED 115000, while 2022 models with lower mileages are listed around AED 205000. Considering the depreciation and the average condition of the target car, I adjusted the estimate slightly lower than the 2021 listings to account for the higher mileage and average condition.