To estimate the price of the 2015 BYD S6 I4 2.4L Standard with 127500 km mileage, I first looked at the selling price of a similar 2016 model with 76000 km mileage, which sold for SAR 17000 on 2023-12-27. Given the 2015 model is a year older and has higher mileage, its value would be lower. Next, I considered the listed prices: a 2015 model with the same mileage is listed for SAR 22000, which is likely higher than the actual market value. Other 2016 models with varying mileages are listed between SAR 19500 and SAR 27000. Considering the depreciation and the higher mileage of the 2015 model, I adjusted the price downwards from the 2016 selling price and the listed prices to arrive at a fair market estimate.