Zeeshan, You didn't mention how many years of experience you have in your field, so cant say if the salary is okie or otherwise. But overall, its pretty good for a family of three. You can have a decent two bedroom apartment in Mansoura or Muntazah in QR 5500/- and for QR 6000/- in Al-Sadd, all of these are nice localities. A Bank Leased Normal Saloon car (Camry,Civic) will not cost you more than QR 1600/month with a five year plan. QR 3000/month should be enough for your grocery. QR 1000/month would your maximum bills for electricity, internet & mobile.

You can also go for the 'search' option on Qatar Living & can have a more clear idea of the expenses.

Advice: Please, dont go for the Nissan Tiida :P