you need 400k in the bank as proof of financial requirement if you are applying from inside thailand for a 3 month non o visa which gives you the yearly extension option after 90 days.
I can't help but feel the single entry 90 day might be better which also allows a 60 day family extension. That's 5 months before u leave and do it again.
The 40k option doesn't work at some immigration offices even though it might say it's accepted on the immigration bureau website. Some immigration offices will only accept the 400k route.
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