It's hard to find one-bedroom accomodations in Doha. The Pearl and West Bay are quite expensive, probably 15,000 QR plus for a two-bedroom place. A small rental car is 2,000 QR per month. Buying a car, figure US prices plus maybe 5-10 percent. Insurance is 4% of the vehicles value per year. Middle-range restaurants like Applebee's and Chili's are about the same as the US. High-end places that serve alcohol are VERY expensive. But, your employer should be paying your rent and transportation.
Mandi