Qatar will always surprise you with extra expenses. You only have a little over $1,000/month for those unbudgeted costs. The American school is more than 40,000QR as are the better British schools. Kids always need something you haven't counted on. Qatar health care only covers the basics in-country so if you travel or go back home you have to pay for insurance. You will owe taxes in the US if you are a resident or citizen. You will not accrue social security or retirement. And you will not be terribly marketable back in the US if you don't like the Gulf. Oh, and did anyone mention the NOC and the lack of any job security in Doha?