non O the one that says for no longer than 90 days. You enter with that visa then open a bank account, deposit 800k baht and then apply for one year extensions of stay ad infinitum.
Technically, you don’t covert, you have to apply for the non o visa. Get 800k deposited in your account two months before you apply. Time is of the essence if you’re in country on a visa exempt entry.
You apply for the 90 day visa and then, once in country, open a bank account, deposit the requisite 800k baht in it and then apply for a one year extension every year.
many people live here full time and don’t pay tax if their foreign income is not assessable. That doesn’t change the fact that folks are Thai tax residents once they stay in country for 180 days cumulatively in one year.