...the school will help to do the work visa, but it's not free
[4/24/2012 11:14:14 PM] Them: would you accept that?
[4/24/2012 11:14:19 PM] Me: How much is it?
[4/24/2012 11:15:22 PM] Them:
about

4000-5000

[4/24/2012 11:15:33 PM] Me: RMB?
[4/24/2012 11:15:38 PM] Them: yes

What I have highlighted in red is utter bullshit. To do the work visa costs MUCH MUCH LESS!

I shall still stick by my initial post. It seems you've misread my earlier post!

'To do the work visa' is the point, not to do the whole procedure, which as you say involves a medical and a Resident Permit, the latter only being issued by the local PSB if the medical report, including an HIV test, is satisfactory, and a Foreign Expert's Certificate is presented along with the medical.
Before the Z visa can be obtained, the foreigner must present a provincially verified letter of invitation, got through the prospective employer.

However, I do agree with you that that 'school' is one to avoid, unless you've no other job offers to consider.