How can a Singapore passport holder transfer 800,000 baht for a Non-O retirement visa in Thailand if she's unable to open a bank account?

Get a letter from bank in SG proving deposit of minimum THB800k equivalent. The amount can be in SGD, subject to exchange rates used by the Thai Embassy for calculation of equivalent amount. Refer to Thai Embassy in SG for list of required documents.

Singapore passport apply with proof of funds in sg for the nonO in thai embassy(sg) Or apply from the thai embassy (canada) if she can proof her residency and funds in Canada hope this helps

Easiest way is to get the Non O before coming to Thailand. They can then open a bank account without needing an agent, as they have a long term visa. They should open the account as soon as they get here and transfer 800,000 baht. They get a list of requirements to extend their stay for 12 months from immigration and when the money has been in their account for 2 months, take the documents on the immigration list to apply. It costs 1,900 baht and there's 1 a4 size form to complete with simple questions like; name, date of arrival in Thailand etc.

Classic Catch-22. Probably best to apply for the Non O in Singapore which will make opening the bank account way easier.

If not you’re probably going to need an agents help.