The information I got and am doing when Canada stopped issuing letters was to open a bank account in a Thai Bank which was very dificult and do an international transfer of a minimum of 65,000 baht each and every month for 12 months prior ot applying for my next retirement visa. I am not allowed to miss any months and make it up the next month. If I use wise it will not show up as an international transfer so I have to transfer it directly from my Canadian bank into the Bangkok bank. We will see what happens next year. I have had a retirement visa for at least 10 years.
I have been living with a Thai woman for 16 years using a letter for my retirement visa. I went to the Bangkok bank with a letter from immigration but they refused to open an account unless I got married