If your life is materialistic, material focused, I would totally agree with you.
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If you live your life focussed on compassion, Tolerance, and Love, your " Rules " become very restrictive.
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Your change over from your Visa shouldn't be a problem.
BUT!
If you are of the age nearing 75 years or if you are already over the age of 75 most definitely to maintain the Thai health insurance you have now for your OA Visa. Once you are getting your O Visa you could reduce your health insurance to a very small cover hence smaller premium to pay.
Unfortunately with an OA Visa here you are forced into a Thai Health Insurance. Very expensive especially after the age of 75 years.
Sooner then later one can expect that the O Visa also would require the same, a Thai Insurance, for a yearly renewal at the Immigration.
Keep in mind: My advise is get as early as possible into a Thai Health Insurance. If you wait till you forced getting a Thai Health Insurance, especially after the age of 75 you are paying astronomical premiums just to get in!
I need to make a seperate Will here in Thailand for my Girlfriend too, that's what the Australian Lawyer advised me to do.
May I ask approximately what costs are involved here in Thailand to get a simple Will, eg 800+ Bank account and house?
Required Testing before Air Travel to the US
Required for all air passengers two years of age or older boarding a flight from a foreign country to the United States
Updated Jan. 27, 2022
If a country requires pre flight testing, the Airlines will check your test results before they let you board the Aircraft, that is my understanding.