What are the requirements for an American citizen to obtain a retirement visa in Thailand?

Please contact one of the moderators to reopen this post if anyone still has something directly related to the original post. Or make a new post.

Because you two are referring to different applications. Those different points of application have different requirements & paperwork.

You are talking about to getting an in-country initial Non-O based on retirement at the local immigration office inside Thailand.

In this case, yes you as US passport holder have to have 800K thb in a Thai bank account.

Your friend is talking about to getting an initial Non-O single entry visa based on retirement at the Royal Thai Embassy/Consulate in US.

In this case, you have to show the 3 months bank statement with more than $10,000.

Either case, he needs to have 800K thb in his Thai bank account for two months when he wants to apply for the very first 1-year extension.

Then as he starts 65k monthly transfer for 12 months while maintaining banked money 800K for three months after 1-year extension and 400K for the rest of the first year, then he can use the transfer method for his next yearly extension.