@Dave ******
You cannot use a stat dec from anywhere byt the australian consulate here to meet the financial requirements of income from abroad (65K baht or the equivalent per month in income) You also cannot put down a bulk amount, you need to put down an amount that equals 65K baht a month. You have three ways to meet the financial requirements INSIDE the country at the immigration office
bank 800K in a thai bank account in your name only before you applying for your 90 day Non-O visa application
OR
use a notarized stat dec from the australian consulate here stating you get 65K baht in income a month.
OR
use a combination of banked money in a thai account and the stat dec to hit 800K baht for the year.