I advise you to check this up with your immigration first, as some immigrations only accept a affidavit within the last 30 days. Just so you don’t risk to get short in time.
Yes I’ve registered that you can’t by credit anymore, but I call unlimited from Thailand to any telephone number in Norway for one month at approximately 10 USD.
Don’t worry I got it too and was in the bank today. Just updated my personal information, address, telephone number email address. Tok a new copy of my passport and I answered several questions confirming I was not a US citizen or had a green card. No questions regarding Tax as I’m just here for 7 weeks this year.
Where do you live in the US? Go to the website of this embassy/consulate and check the requirements for a Non O visa. As said you probably will be able to apply based on a combination of funds and income. Most embassies allow this.
As said you’ll need to bank the required 800K baht for your first year extension of stay. Regarding the combination method for the second year it’s a bit immigration dependent. Several immigrations allow it, but not all.
You can probably apply for a 90 days Non O through the Thai embassy/consulate that serves you with a combination of income and funds in total equal to 800K baht in one year. But you’ll need 800K baht for the first year extension of stay in Thailand. For your second year extension of stay you can change to the income method by showing proof of twelve months consecutive transfers of min 65K baht a month. If you can’t meet the required monthly amount, several immigrations -but not all- accept the combination method if your monthly transfers and funds in total can meet the required 800K baht within a year.