Did you email the online copy of the TM-30 to the immigration agent that takes the photos, so they can print a copy for you to take to the counter? I was just at the Chonburi immigration office this morning to get CoR to purchase a car and had to reprint my pdf copy.
I believe it has to be in a regular account and not an investment account. You can get all your official answers here: Official Website of Thailand Electronic Visa
the 500k baht (approx $15k USD) requirement for DTV can be in your US bank account. But you have to show proof (bank statements ) of these funds being in that account for longer than 3 months.
Also, keep in mind that you have to apply for the dtv outside of Thailand through the Thai embassy or consulate. So that means you can apply from your home country or if you'll be staying in Thailand, you can also cross over into a neighboring country and apply.
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