Moving over (Doha)

i have just been offered a job in Doha and hoping you could help me make my decision to come. i have done quite a bit of research, and spoke to a few people so i know quite a bit know but the big one as always comes down to money. i have a wife and a small child starting school next year and would like to know in rough terms how much i need for 3 bed villa, 4x4/quality vehicle, gyms/entertainment. Sorted now with costs for schooling. Any help would be much appreciated, even in very generic terms as searching agents i find on google i get vastly different ideas of cost.

Many thanks in advance