I travel to China frequently and have recently rented an apartment in Qingdao. Cost of living varies by city, with Beijing and Shanghai being the most expensive. The 8,000 RMB figure for these cities is about right. I know a female lawyer in Beijing whose salary is 8,000 per month. But there is a lot of variance by city.
But back to Qingdao. A fairly good salary there may be 5,000 per month. I know a lot of professional people who make 2,500 or 3,000. I rented a two bedroom apartment, furnished for 28,000 RMB per year. It is quite nice, on the first floor (you pay a premium) of the apartment complex. Of course, I had to have a Chinese employee negotiate the price or it would have been at least 50% higher as I am a lao wei.
While in Chengdu recently I was amazed at how cheap things were there. It seems to be a great place to live, and the women are very beautiful, in my opinion.
Hope this helps.