Young women approach you in the fancy shopping district near Wangfujing subway station asking if they can practice their english. You wind up in a shop of their selection and have a few cups of tea. Then the bill comes and it is absurdly high.
I got nicked for 690 RMB for a few beers and drinks. Small potatoes compared to what others have reported but it still stung. The shopkeeper brings little snacks - stuff that should be free. Turns out that tiny plate of almonds cost 139 RMB - about $20 US.
If you get stuck like this put down half the total and tell them and the shop owners that is all you are paying and walk out. Let them figure it out.