Am a Ghanaian(trader) planning of relocate to China and work there

Adonis, to work in China, you have to get a company there to hire you. Only after that, you can get the work license and invitation letter from duly authorized unit, which are necessry for applying the Z type entry permit. So if you don't know any company there, I'm afraid you can't get the Z type.

There is no wage limit for expats. The wage level depends on your work type and capability.