Hi. I am in China on a tourist visa and have been offered a job.

My employer can provide all the paperwork, but I thought I would have to return to the UK myself.
1) can I post my papers and passport to you and have the visa sent to me in China
2) If not, I see that some people are talking about Hong Kong. I was told that this was no longer possible. Can you provide details on how to do this.
3) If this is also not possible, I see that you say it is possible, but difficult to "upgrade" a tourist visa. Is this still the case? Can you provide details?