Your monthly budget will look like this:

Housing Rents exorbitantly high in Qatar. If you want decent place to live you have to spend around 7500 to 9500.

QAR (Per Month) For 2+2 Family
7,500 House Rent (Furnished)
2,000 Groceries+ Misc exps.
1,600 School Fees+Other Exps.for One Child
1,500 Car Hire / OR Loan installment + Petrol
33 Land Line Rent
50 Mobile Rent OR Prepaid Card
150 Water Charges
150 Electricity
200 Internet at home
75 Television Channel Connection
120 VOIP Call Card to call home country
200 Car Insurance (2500/12)if you own your car
_____________
13,578 Total

One Time Exps.
1,000 Deposit for Water Connection
1,000 Deposit for Ele. Connection
7,500 House Rent Deposit
2,000 Driving Classes Fees (Appx.)
250 One Time Mobile activation Charges
_____________________
11,750 Total

You may negotiate for Education fees reimbursement. You may cut down your exps. in some areas but by and large it will remain between 10,000 to 11,000 minimum. It is also true that after joining you may not been able to negotiate your terms. Don't feel shy to negotiate your terms before joining.