Read Tod's post again. The METV holders he mentioned sure sound like they were affected by rule changes. Also, there isn't always an applicable long stay visa for legittimate multiple trips. Those days *may* be over and that's a loss for everyone.
The return details is a non-obligatory field (no asterisk), but as Lloyd says it MIGHT be your airline that demands to see your return ticket. There's no fixed rule. I came in one-way ten days ago and the airline did NOT ask about my return ticket but they DID demand to see the TDAC.
Take fair warning from others' replies that it may be an uphill struggle for you if your potential employer is so completely clueless about employing a foreigner. The idea that they sent you to your own embassy to ask about working in Thailand is embarrassing.
- Brilliant, Monsieur Poirot, but I'm capable of remembering which passport I'm travelling on. Entry stamps are a great help with that 🤨. All passports used are in the system, and they are free to ask to see the other one/s.
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