not sure for Chinese. As said before, Chinese ppl are reqired to go to their country for visa. I know they can have 1 tourist visa for Thailand in Vietnam, but its an exception, and idk if ED can too. Asking embassy.
yes, and i think need go China. But, in Covid time, they introduce a fee of 10k thb in order to swap visa from inside the country, maybe still available.
You cannot work "officially" in the compagny you own without work permit.
If you need to be "in control" can have 2 types of share, one owning but without vote, the other one owning too, but can vote. This way you have 100% control.
In case of trouble, you can sell, or anything you want (legacy).
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