Katrin,

If you are only here for 7 months there is no point in buying a car. It is better to rent one for that period of time. It will cost approx QR2200 per month for something decent.

Will you need a car? This place has no public transport to speak of and you would be crazy or suicidal to ride a bike. You could use a driver which would cost about the same as renting a car. Doha is a very cae centric place and it is impossible to get around any other way than by car.

If you could stand to drive here (and it is not like Sweden) I would recommend renting a car. At least you would have full insurance and a replacement for the time someone inevitably drives into the back of you!