how much is the visa, what are the requirements and how long does it take?

It costs BWP 500 for a single entry one. It takes 10 working days to handle your application. You should apply for a M type. The required documents are:
1. your passport. It should be valid more than six months and have two blank pages at least.
2. a recent passport photo in light background
3. a copy of your passport information page approved by your immigration bureau
4. filled application form
5. round-trip air tickets and hotel booking
6. your bank statement, in which you should have at least BWP 40000 inside.
7. invitation letter from any Chinese trade company