Leslie Wheeler Visa exempt is probably what you have unless you applied for a visa before you left your country. (Was it USA?) Just be aware that day one is the day you arrive, not the following day. 
Jumper25 I believe the ฿800,000 does not have to be certified as foreign transfer. I used an agent for my one year stay extension, but I used my own funds, which I transferred in through Wise. I did not get a certificate of foreign transfer. And I haven’t seen that rule anywhere. 
Ria Feel I think the word you’re looking for is extendable. You can apply for a one year stay permit with the non-o retirement visa once you’re in Thailand. It can’t be done on the website. And it’s a somewhat complicated process. I just did it.
I did the Thai E visa through the New York office. First they wanted the equivalent of ฿800,000 showing in my account. That was listed as a requirement on the website. Then they wrote to me and asked for three months of statements from my bank showing at least ฿65,000 with the equivalent in deposits each month. I just pulled my statements from my bank website and uploaded them.
I don’t think going there in person is worth the time and effort. Just follow the instructions on the website. If they want more information, they’ll contact you. 
Greg Gursey the application said I needed to show the equivalent of ฿800,000. And then they wrote to me and asked me for three months of income.
I don’t remember exactly the dates but I seem to remember I applied a month before my flight and it didn’t come through in time. It took about another three weeks so almost 2 months. I came over as a Visa-exempt tourist. I had to leave Thailand and re-enter to activate the 90 day visa. Someone on this forum told me you’re not supposed to do that, you’re supposed to wait wherever you applied, but I didn’t know. And I was planning a trip to Vietnam and Laos anyway so it all worked out.
I don’t know why it took so long in my case. I think it’s uncommon. I wrote to them twice saying hey I’ve got a flight booked. Can we move this along please? And both times I got a kind of standard issue response saying we have received your message and we are looking into this.
Bradley Gibson thanks for all that info. I already sent the ฿800,000 via Wise. I was at the branch opening my account and did it all the same day. I had to split it into two transactions, I think because my bank has a transfer limit.  I don’t remember, but it didn’t seem like I was charged very much. I had already converted the money to Thai baht in my Wise account
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