Depends on the individual.Some people spend a lot on
luxuries and expensive brands and excuse me for using this word, 'splurge' heavily.I agree that housing is quite expensive here but definately not food.There are many places here in Doha that you can go to and eat without spending a lot of money.As for buying a car is concerned,i would suggest you do a bit of exploring before you make up your mind.Good Luck!