To estimate the price of the 2021 GWM POER I4 2.0L Turbo Charged Luxury Double Cab 4WD (Top) with 30000 km mileage, I considered the listed prices of similar cars. The closest match is the 2021 GWM POER I4 2.0L (Diesel) Luxury Double Cab 4WD Diesel (Top+) with 49000 km listed for SAR 68000. Given that the target car has lower mileage, it should be valued higher. The 2022 models listed range from SAR 67500 to SAR 77000, with varying mileages. Adjusting for the year difference and mileage, the target car's price should be slightly lower than the 2022 models but higher than the 2021 model with higher mileage. Therefore, I estimate the market price to be around SAR 72000.