To estimate the price of the 2015 Renault Fluence I4 1.6L PE (Base) with 135700 km mileage, I considered the following data points: 1. A 2015 Renault Fluence I4 2.0L with 148400 km sold for 15500 SAR on 2023-10-20. This car has a larger engine, so it likely sold for more. 2. A 2015 Renault Fluence I4 1.6L with 145500 km sold for 11500 SAR on 2023-10-22. This car is very similar in terms of engine and year. 3. A 2014 Renault Fluence I4 1.6L with 173000 km sold for 9000 SAR on 2023-11-15. This car is older and has higher mileage. 4. A 2016 Renault Fluence I4 1.6L with 125000 km sold for 20000 SAR on 2023-11-23 and 2023-12-05. These cars are newer and have lower mileage. 5. A 2016 Renault Fluence I4 1.6L with 310000 km sold for 17000 SAR on 2024-01-21. This car has much higher mileage. 6. A 2015 Renault Fluence I4 1.6L with 291000 km sold for 14000 SAR on 2024-07-23. This car has much higher mileage. Based on these data points, the most relevant comparison is the 2015 Renault Fluence I4 1.6L with 145500 km sold for 11500 SAR. Given the slightly lower mileage of the target car, I adjusted the price slightly higher.