Hello, I'm an American citizen working in Shanghai with a US-based advertising agency. I have been in China on a tourist visa, extended almost to 90 days now. I want to continue the business relationship and my company has offered an invitation letter for a 12-month multi-entry F visa, with their stamp on the letter. The visa agency in Shanghai that was recommended to me says on their web site that it's difficult to fulfill the L to F conversion in Shanghai as of July 1 2010. They recommend going to Hong Kong.
I am also wondering if the invitation letter, with the company stamp, is sufficient. Some posts here mention an authorization letter from the local government as well... I don't want to go to Hong Kong and have my application refused! Any advice appreciated.