The visa fee is HK$150.
The requirements are:

1. Valid passport (at least six months before expiration) with blank visa pages.
2. Completed Chinese visa application form, one colored passport photo taken in the last six months.
3. Under some circumstances, the applicants may be required to provide financial proof, a copy of Chinese hotel booking and return flight ticke.
The visa application process takes 4 working days, and ther eis also express service.