Hello I want to Apply for a Business M type to China,

so below are the documents that I have already prepared:

1) Passport Valid for more than 6 months
2) Letter of Invitation stamped from a Chinese Company
3) Commercial Register of my company
4) application form already filled
5) Photo Passport
6) Ticket showing my scheduled routing
7) Bank statement showing a balance above 6000USD
8) Hotel Reservation in China

- Do I need any additional document?
- Is it possible to get a 2 Years Multiple entry visa valid for 2 months each entry? If not 2 years is it possible to get a 1 Year Multiple entry one valid for 2 months each entry? (It is very important for me to be allowed to stay 2 months in China).

Please note that in the past I already got a visa which allows me to stay 60 days in China.
Thanks a lot in advance for your assistance.