it doesn't have to do with the bank as much as it is related to the value of the car.

The interest rate differs slightly between banks. So, to end up paying 500QR per month, which covers your premium+interest, you need to find a car valued at 28,500 QR. I'm assuming your interest rate is 8% and you took the loan over 6 years.

You can use this link to play around with different scenarios;

http://www.cars.com/go/advice/financing/calc/loanCalc.jsp?mode=full