I live in Thailand with an O-A marriage visa. Where can I go to a Royal Thai consulate that is outside Thailand. Of course border must be open. What documents are requred to enter country, and what is required to come back to Thailand.  Also shat documents do I need for the actual visa application.  Has anyone done this recently?

Don't leave Thailand. Obtain extension at immigration. 

There are financial requirements with money in bank method and also using income method.

I assume non O-A marriage means your extension based on marriage.

 

A OA visa is based upon retirement not marriage.

If married to a Thai you could change the reason for your extension of stay from retirement to avoid the insurance requirements for a OA visa entry.

There is not nearby country you easily travel to if allowed entry. You might have to return to your home country to get a non-o visa.

You will need to have a certificate of entry to return to Thailand after getting the non-o visa, a reservation at a ASQ hotel for the 14 day quarantine, a vivid 19 test and $100,000 coverage for covid 19 for 90 days.

Why do you want to apply for a new Visa at a Thai Consulate?

 

If you originally entered Thailand on a Non Imm O-A Visa, then you can just apply to extend your permission of stay at your local Immigration office.

If married to a Thai you apply on that basis.

The financial requirement is 400K deposit in a Thai bank for 2 months prior to the date of application, OR 12 x 40K monthly overseas transfers to a Thai bank.