I was here on an OA for 6 years. For both the O and the OA you typically eventually end up getting 1 year extensions. While getting 1 year extensions the only difference between an O and OA is the required health insurance for the OA. There was no insurance requirement when I got my OA in 2017 so now I would recommend the O as a better choice. With an O visa you have more flexibility about insurance choices if you choose to have insurance.
Now I am on the 10 year pension LTR visa. That also has an insurance requirement though that particular requirement is a little more flexible. The LTR has some steep financial requirements. It is worth looking into as a possible option.
“As a holder of the "Wealthy Pensioner" category of LTR Visa, you are exempt from the Section 41 paragraph two foreign source income tax law, and therefore, you have no tax obligation in Thailand on any of the pension monies that you wire transfer from the US to Thailand. This exemption from the Section 41 paragraph two foreign source income tax law is provided to you under Royal Decree (No 743).
You also do not have to file any tax return in Thailand. For you to see this, see the attached PND95 Tax Return form. You'll see at the top of the form that only the "Highly Skilled Professionals" category of LTR Visa holders are required to file the PND95 tax return (not the "Wealthy Pensioner" category of LTR Visa holders).”
You need the 800,000 baht deposit to get a 1 year extension of an OA visa. You can use your home country bank deposits to get the original 1-2 year visa.
As an American I just sign it myself and send it back. I’ve got my proof of life letter waiting for me in Thailand. I will return tomorrow and sign it in the next week.