To estimate the price of the 2020 Toyota Corolla I4 1.6L XLI (Base) with 138000 km mileage and average condition, I first considered the selling price of a similar car with 136593 km mileage, good condition, and the same variant, which sold for SAR 53000 on 2023-11-07. Given the average condition of the target car, I adjusted the price downwards. Next, I reviewed listed prices of similar cars: one with the same mileage listed for SAR 57000, another with 136593 km listed for SAR 56500, and others ranging from SAR 45000 to SAR 57000. The most relevant listings were around SAR 53000 to SAR 57000. Considering the average condition and the fact that listed prices are generally higher than selling prices, I estimated the market price to be slightly lower than the selling price of the good condition car.