In Beijing, there are some illegal tour buses offering day tours to the Great Wall. You will have a terrible trip once you get on it. To promote their illegal tours, these sales people hand out business cards to passing-by travelers who want to go to the Great Wall tour around some big destinations like Tiananmen Square, the entrance of Forbidden City…
Very often they use their “unbelievable low price” to attract those “blind” tourists. But once you come aboard their bus for the Great Wall, they have to make you pay additional fees again and again. Sometimes even the Great Wall is not real Badaling section!! You are kindly advised not to take their card if you happen to meet them. Most of the black tour buses don’t offer English speaking tour guide service.
These organised tours by hotels or local tour operators with English speaking tour guide service are a good introduction to the sights, especially to non-Chinese speakers.
I suggest that you use the slightly more expensive yet reliable organized bus tours through your hotel, or local tour operators. Avoid Taxis and private individual tour guide, a promise means nothing!
Though there are some shopping stops on these organized tours and it can be annoying, no real pressure to buy and just be polite, decline, and move on. So don’t be put off by these stops. Keep a sense of humour and just remember although they want to sell you something you don’t have to buy.