Of that 8500QAR, about 4000QAR will be spent for the cheapest family accommodation. Will need around 1500QAR for grocery, another 1000-1500 for transport/telephone/utilities etc. If you have children, Indian schools here would be atleast 500QAR per month.
Now do your calculations.
If you can, negotiate for furnished family accommodation, children's education and yearly vacation tickets for family.