What are some Chinese Business superstitions?

Some numbers means something.

8 represents happiness, so to make people happy you pay them with numbers containing the most 8 possible. 18,88 is a great number because in Chinese it sounds like "you will get rich, rich, rich". On the other hand, you should avoid 250. It means "stupid" when said in a certain way (erbaiwu instead of liangbaiwu).

Also one thing I have observed is that you mostly don 't say numbers aloud. You write them down. Calculators or cell phones make great writing boards to negociate.