3) No idea. Recommend 1 or 2. 3 would only be of interest if you wished to continue working while in Thailand. You cannot legally work on a retirement extension of stay. Personally, I don't think 3 would be the easy way to go, but it depends where you want to end up. Retired -> retirement visa/extension. Still working -> business visa.

2) You would get stamped into Thailand for a 60 day stay with a Tourist Visa and you could apply for 30-day extension at immigration for 1,900 baht.

I don't like the word conversion, but with a visa-exempt entry or Tourist Visa you can apply for a Non-O visa in Thailand for 2,000 baht if you meet the underlying requirements for the visa (such as being over 50 - retirement - and meeting the financial requirements). This Non-O visa gets you a 90-day stay which can be extended forever, for a year at a time for 1,900 (you must meet financial requirements). You would never have to leave Thailand again if that were your wish. Trips outside Thailand would require a re-entry permit (1,000 baht) to re-enter Thailand and resume your permission to stay granted on your extension of stay.

How to do this, at least in Phuket is explained at the following two links. First is getting the Non-O in Thailand, second is getting a retirement extension of stay.

1) As a US citizen you can arrive on visa-exempt entry and get stamped in for 45 days (it will be 45 days until at least the end of September, anything else would require a change to the law). You can extend for 30 days at immigration for 1,900 baht. Visa-exempt entry is by far the easiest as don't have to get visa from embassy/consulate.

I have both. Nice to have. No real immigration issues, though you will likely need to get a Certificate of Residence from immigration to apply for the yellow book.

My yellow book was done at the tessabahn office, pink ID card at the amphur office. In Karon, Phuket.

@Bryn *******

Yes, if you're from one of the countries that don't provide an embassy income letter (US, UK, Australia) then you have to make a year's worth of monthly deposits in excess of 65k/month before you can extend your extension on that basis. Once deposited the money may be completely withdrawn each month.

Now can we see the details?

And for what it's worth, I approve their approval of it. ;-)

How about just an article on the Phuket sandbox ONLY. Then maybe have an article about the 3 islands. A separate article. You know, so people might not get confused. Really, clarity is a virtue. Sorry, this stuff is not really rocket surgery, but you'd be forgiven for thinking it is because of how convoluted the explanation of the rules is. Make things simple. Make things clear. Don't try to do everything at once. Do one thing at a time well. Then do the next thing well.

@Garrett **********

No, that's not the way I read the article. [I really wish the article would have just addressed the Phuket Sandbox and not the 3 islands. starting later.] As I read the article you take a test at the airport and you must remain in your hotel room until a negative test result is received. I can't see that taking 3 days, probably overnight - don't know. Then the article goes on to talk about the 3 islands (so not the Phuket Sandbox) and that's where you can see the 3 days quarantine in your hotel room.