Hi, we have done japanese e-commerce sites before. so adjusting to the Chinese sites wont be any problem, we can work on a private cms system that allows all available languages to optimize the support we translate the charsets so the entire site is in any language seo friendly even the menus.
Depending on youre project for e commerce sites we have never charged over 6000$ that includes design and any functionality you want.
We can give you warranty on the site, warranty details we do discuss before starting on the work.
Price will depend on total project and will be definitive after descent project discussion.
If you want high quality and sites that are future proof, pls contact me.
And yes we can do more than one project, if language barriers are a problem we do work whit special translation offices.