In China advertising can be easy. People just write their telephone numbers on walls in the streets and put next to it, what they are selling. I suppose, people do call, otherwise they would´t continue putting up their phone numbers on there.
Even inside houses they put their numbers. I took this picture in an old living compound in Beijing. I find, this one turned out to be like a piece of art :). And – feel free to call, if you need anything. I don´t read Chinese characters (yet), so if you know what they are offering, please tell me!