Just so that all the facts are correct;
Shenzhen now have 8 expats. The salary is USD5000 after tax. Agency A provides for apartment accomodation and 5 tickets per year. Agency B gives you the USD1000 (probably in RMB), says go find your own accomodation and provides for only 2 tickets per year. Agency B is yet to muscle in here yet but rumour has it, it may soon.
They are still very interested in employing about 20 more this year. A few have failed the medical and lots have failed the sim check, which is done raw data with emergencies at a very challenging airport.
Tax may be not what it seems........