F Class Visa Inquiry

I am intended to visit China, zhangjiagang city jiangsu province in order to inspect and buy water a bottling plant. I would like to apply for visa on "F" class and therefore, please let me know, (visit period is 7 days and 1 person. visit behalf of my company and I am CEO)
1. I am going to cover all financial , how much i should show in my account ( bank statements)?
2. Need to reserved Hotels and Air Ticket before visa to proof with application?
3. any type of letter need from my Sri Lanka company? if yes what?
4. letter of invitation and verification will provide by the China company? any other letter needed?
5. letter of verification should attested by any authority in china, before process?

I look forward hearing from you soon