Chinese Visa in Kathmandu

I have a few questions, so I will number them. Thanks for your reply. We leave for China on October 2nd from Kathmandu to Beijing, and we are looking to visit Hong Kong and Mainland for 40 days.

#1. We get back from our 10-day ABC trek on the night of Friday the 28th. Will we be able to use the Extremely Urgent service to get our Visa started/completed on Monday the 1st? Is that cost of $177 still current?

#2. Aside from a valid passport, and our flight information in digital form, what documents do we need? Do we need an invitation from a friend who lives there?

#3. Can we process this Visa through a Travel Agent in Pokhara? If so do you know which travel agent is the cheapest to get that done?