Housing fees are not enough, 10-12K QR is minimum for any place decent. Your 25% education cost will be high for 3 children, a car will cost you 2K QR per month.

So from the 18K QR salary, you will spend 4K QR per month on extra housing cost, plus electric, water, phone, internet, mobile, etc. You will spend 1K QR per month on extra car cost and depending on the school fees, which are going up, another 500QR per month.

Food costs are not cheap, clothes are not cheap, so you will not be getting ahead at these numbers.