To estimate the price of the 2021 Nissan Patrol SE Titanium V6 4.0L with 90878 km mileage in average condition, I first looked at the selling prices of similar cars. The closest match is a 2022 Nissan Patrol SE Titanium V6 4.0L with 14964 km in good condition sold for 230000 SAR on 2023-09-11. Considering the year difference and higher mileage, I adjusted the price downwards. Another relevant data point is a 2020 Nissan Patrol Platinum V6 4.0L with 50700 km in average condition sold for 180000 SAR on 2024-02-15. Given the target car's higher mileage and similar condition, I adjusted the price slightly downwards. The listed prices for similar cars range from 123000 SAR to 198000 SAR, but these are generally higher than actual selling prices. Taking all these factors into account, I estimated the market price accordingly.