Cost of Living

What is the cost of living in China?  What is a middle class salary?  When do people start becoming rich?  What is poor in China?  These are confusing questions that my old sitemate and I often wondered about. Currently Peace Corps volunteers get free housing, free medical care, and a monthly living allowance of about 1500 RMB ($220).  We are single university teachers who do not have a lot of expenses compared to our counterparts with families, mortgages, and children.  At our university, teachers receive a salary of about 3000 RMB/month ($440) plus bonuses. My students said that the tuition and cost of dorm rooms at our university has jumped from 3500 RMB ($550) to 6000 RMB ($880).  This rate is one of the lower tuition rates at our university since English majors will become English teachers.  If a student receives a non-teaching degree, tuition becomes more expensive.  Students are required to live in the dorms sharing a room with 6-8 people and pay the dorm fees even if they rent a place off campus.  One person meals cost anywhere from 1-6 RMB ($0.14-$1) which according to the students have increased in price by 1 RMB.  Showers cost 6-8 RMB ($1-$1.25).  Internet bars cost 2 RMB/hr ($0.25).  If a family has a car, does it mean they are rich or middle class?  If a family eats at KFC or at the chicken fast food places in the city, does it mean they are rich or middle class?  Meals for one person at chicken fast food places cost 15-30 RMB ($2.25-$4.40).   Are street sweepers, street vendors, and people who work in the supermarkets and restaurants, poor? From students I have heard for these jobs people make about 300-500 RMB ($45-$75) per month. Questions that I haven't been able to get a clear answer about are How much does it cost to buy an apartment?  How much is rent?  Many of the juniors and seniors who want to study and have 24 hour electricity will spend about 100 RMB renting one room that they will share between two people. It is really confusing.  What do you think?  Are Peace Corps volunteers in the lower middle class or upper middle class or in the rich bracket of China's salary class?  In Africa, it was clear that Peace Corps volunteers were in the upper middle class approaching rich.  In China, I am not so sure. Estimated RMB exchange rate used in calculations:  6.8 RMB/USD