I will leave rent out because that is very particular with the individual choices.  But assume maybe as much as 1000 Rmb per month for food, maybe in the 300 Rmb every two months for electricity, 50 Rmb per month for gas, maybe 15 Rmb for water, I pay 118 Rmb per month for my home phone line, the cell phone (with 388 minutes per month) and 4M broadband internet connection.  Transportationj maybe another 100 Rmb, then clothes, laundry, and other incidentals. 

I do not live in Shanghai, and I do live like a King, and do as I please and do travel a lot, but my budget is 5,000 Rmb per month including rent.  And I do make it almost every month. 

Of course, traveling is not within the budget. 

A decent 1 bedroom apartment, quite near to the citycenter will run at around 3500 RMB per month. Electricity mainly depends on how much AC for heating or cooling you use, can be 200-300 RMB in hot/cold months. Water is cheap, maybe 20 RMB per month. Mobile phone 50 per month, if you use a lot. Internet 100. Eating depends on: eat at local restaurant will be less than 20 RMB per person/visit; foreign food runs at last 3 times aboe this price. As rule of thumb, u can spend 1 USD per meal, but u can easily spend up to 100 USD per meal and person, everything can be found Transportation depends on if you need to travel a lot, subway (from 3-10RMB) or bus (2RMB), or taxi. If you plan to take taxi, even if it seems to be cheap (14RMB for 3 km,) you will end up spending a lot by the end of the month). Additionally if you like drinking in bars, expect to pay 40-50RMB for beer, 60-100 for cocktails.

How much you spend in Shanghai depends on your lifestyle