In response to must be based in country (The chicken & egg application problem)

This is a good post, that could easily be applied to China.

Many schools will say they prefer teachers IN China, but then good luck getting a work visa if you never had one before, or if you entered on a tourist visa. In english, I called this, shooting themselves in the feet..........they want teachers, but their recruitment/visa procedures are a joke, both inside China and abroad.