As UKEngQtr mentioned that West Bay area is quite expensive. Apartment rents starts from over QR 12000/month. If you want to have accommodation in other areas of Doha, you can visit the Classifieds Section of this website here:

http://www.qatarliving.com/classifieds/accommodation

Or, can check the Classifieds of Daily Gulf Times here:

www.gulf-times.com