Never been ask funds, neither at normal entry, extension, in 30 years...AND IF I WOULD, have my phone banking, with proof of money, on my Thai and foreign bank account, Gold card (which you not get if no funds. Sure, never think it cannot happen to you, but I not know many people asked for funds, but very important is the exact place you stay. Visa, always bank statement.
Garrett Greenwald , If you want to persist, I can do nothing for you. I traveled in November. Brussels - Frankfurt - Bangkok. In Brussel, I was denied boarding pass for Bangkok, as it will take him an hour to check if indeed, I would be on that plane out of Thailand. Told me to try in Frankfurt. I refused, and said I was not going to stand in line there again and pick up my suitcase. He then finally phoned, checked, and that was not done in an hour, but 3 minutes. Why take the risk, if even there is the smallest possibility, the COULD check it? Nort worth 10 dollar, don't you think so? If you flight is cancelled already, you are not travelling, point.
Very bad advice! If you cancel the ticket BEFORE you fly, you are not registered on it. And airline check this now. As with rent a ticket, you are listed, when you travel, then you cancel, AFTER you took the outbound flight, and then just pay 10 € or so. I had the problem with Lufthansa, her in Europe, they not wanted to board me, were even too, lazy to check, if my flight was real. I had to insist, and then they checked not my paperwork, but did actually, see if I were on the list on the aircraft I had to take later.