You are in China and decide to check out the street market. As you are walking through what seems to be hundreds of vendors, you're approached by a woman who speaks very good English. You're happy to have someone to talk to and she gives you a few great tips on what to buy and what not to buy.

After a good chat, she recommends a tea place on the next block where you can have a drink and rest your feet. The person working in the place will bring you a selection of teas in several kettles and cups. She may show off a little, pouring hot water from as high as possible while maintaining a conversation in Mandarin with your friend. It might look like a 3-min ceremony, filled with all kinds of skilled moves.

Then, when you're done your time there, the server drops of a $140 bill. Your "friend” will also look surprised, apologizing for the inconvenience. But she's not really sorry or surprised; she's their employee.

How to avoid: always be wary of people who walk right up to you and start speaking English, especially if they recommend you go places. You could get trapped in a taxi or end up stuck with a bill that's higher than you can afford. Don't fall for it.