Congrats! Very useful application breakdown. Prepare to show a copy of your DTV, TDAC on arrival. No problem, staying in Vietnam for a month or so, you have 5 years to enter Thailand.
The 20k cash is often asked for those on visa exempt, not seen posts by many DTVERS told to show the 20k. I saw an announcement post today though that immigration is going to do more 20k spot checks on airport/land arrivals. Paying for 'safe entry' where no questions are asked is an option.
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