To estimate the price of the 2015 BMW 520 Twin Power Turbo I4 2.0L Standard, I first considered the selling prices of similar cars. The most relevant data points are the 2016 BMW 520 with similar specs and condition, sold for SAR 55500 and SAR 54500, with mileages of 167000 km and 251000 km respectively. The 2013 models sold for SAR 31500, SAR 32000, and SAR 35000, but these are older and less relevant. The 2014 model in good condition sold for SAR 55000, but it had lower mileage. The 2016 model with 106000 km sold for SAR 66000, but it had significantly lower mileage. The 2015 model listed for SAR 62000 was delisted, indicating it might not have sold at that price. Considering the 2015 model's mileage of 180500 km and average condition, I estimate its market price to be slightly lower than the 2016 models with higher mileage, around SAR 54000.