You don't need to earn a lot of money but still can live comfortably in Beijing.
What you need is only hundreds of dollars to rent a house in the center of the city, and some odd money to buy some delicious food, cheap drinks and cheap DVDs. From hot spicy Sichuan Cuisine to cuisine of southwestern minority groups, flavors are various.
Your salary and that of your foreign teacher colleagues is high, there is money for expensive trips, and they will probably act as your travel agent, buying plane and train tickets.
Always bring copies identical to the one supplied to the interviewer.
With the development of the HR market of China, interview is becoming more and more important in job-seeking.