As others have stated it is not necessary, but if you want to change to the monthly income method in a year, you need to deposit 65,000 Baht per month for 12 months to qualify next year.
me too. I did it before it became impossible to open a bank account in Thailand without paying an agent. Much easier now to get the non O before you come to Thailand.
there is no insurance requirement with the non O visa, you are confusing it with the non OA (hardly anybody uses that anyway). The non O - 90 day is the retirement visa, once here he can extend his stay by 12 months, but this is an extension based on retirement and not a visa.
It's a very simple process, if you arrive with your non O visa, you can then open a bank account, deposit 800k, wait 2 months then apply at immigration for the extension of stay based on retirement. I have extended mine 3 times now and it takes me less than an hour. It is 1 simple form to complete and lots of photocopies of your documents etc, no need for an agent. Good luck.