Maybe you could make around 20,000 RMB at a university per month in Beijing. However, it may be possible to make $40,000 dollars a year if the job was with an American firm.

Actually in general Universities in Beijing pay peanuts, as with Universities throughout China. You won't be making the big bucks working at any Uni, and in general you won't make the big bucks working in China period. You can do OK, but only a few make anything near the kind of money that is being talked about here. Real International schools may pay close to 20,000 yuan a month, but jobs like that are like diamonds, very rare and never advertised.