It also comes down to how well you fare at dealing with places that don't expect foreign tourists.

We have often eaten perfectly good meals in Shanghai for under 10 RMB/person. Nothing fancy but no complaints. I wouldn't want to try it without speaking Chinese, though. (My wife is a native speaker.) We almost always use the bus to get around unless there are 4 of us. (At which point a taxi is often competitive with the bus if you would have to take two buses.)

Many buses call the stops in English as well as Chinese but you had better know where you are going--the English is a recording, the driver won't understand you.

As has been mentioned upthread, tourist site prices are often way out of line with other costs.