well, u r right to some extent, if u are looking for a 2 bedroom fully furnished apartment it would definately cost u more than this in a decent area,I live in Matar Qadeem (that is the airport area)in a fully furnished 2 BR apartment and the rent is 7,600(inclusive of water and electricity bills) although it is the airport area but the location where we live is quite nice,and we don't hear any kind of noise from the landing and taking off planes,so i would say for a 2BR F/F residence u must expect atleast 7,000 QR but if u need a one bedroom flat that is easy to find in 6000 in main city. The average range for normal furnished flats starts from 5,500 (that is an average furnishing) check www.alemadi.com.qa for better judgement of rents in reasonable areas. hope this helps u.
Good Luck.