Do I need a Police Clearance and Medical Certificate for a Non Immigrant O Visa in Thailand?

Sorry a bit Off topic.

You need to have your funds sitting in your Thai account for two months when you apply for a 1-year extension. That means you only have one month to sort out your bank things. If this is okay, a Non-O single entry would be fine for you.

But if you are not confident to sort everything out for your 1-year extension application just in one month, maybe better to get a single entry tourist visa as mentioned above. You will be stamped for 60days and you can get a 30days tourism extension if you still need extra time. You don't need to have your funds seasoned when you apply for the first in-country Non-O visa from tourist visa entry. Just one day in the account would be enough. That two-month requirement is only for a 1-year extension.

I got a non o retirement visa from Thai embassy in London in September. It’s very straightforward and quick as long as you meet the requirements. You need to have health insurance to cover you for the duration of the initial 90 days in Thailand. You need to open a Thai bank account quickly to season the 800k baht for 2 months before you get the yearly extension (so you actually don’t have 90 days to open a bank account).

To get a 90 day Non-O visa (at your thai consulate or inside the country) there is no requirement to have a police check. That is for an O-A or O-X visa only.

The non O in uk doesnt need the police check and is pretty straightforward to get. Cant remember the updated regs now regarding insurance but the extensions in thailand dont require it. The London embassy website is quite good and has all the info if you dig around a little. Getting the extension in thailand is no hassle provided you deposit the 800k in good time.

As James says your alternative is tourist visa and then the non o in thailand. I did mine in the uk.

Simply...get a tourist visa ...that gives you 60+30=90 days to sort out your in country Non O and one year extension of stay.

...No medical certificate...

...No special insurance required other than that of the Thailand Pass to enter Thailand.

...No police clearance required.

IF you can get the Non O for retirement in the UK...go ahead and get it if easy for you.

But do not get the OA...as it does have the many added requirements listed above.