Check the website of the american school of doha and look for the tuition fees as a guidance.

A (decent) compound villa will cost you at least QAR 12,500 per month.

You will need two cars as public transport almost non-exisiting

Your basis salary seems at the lower end.

Family life in doha is pretty dull and the working environment is quite different to what you are used to; f,e, an exit permit is required from your employer every time you want to leave the country (even if it is a pure private weekend trip to Dubai f.e.).