The tm30 is done online at the listed website. I was told to do it myself as landlord is difficult to find! They have a leaflet inside immigration to help you with it. I was unable to print it as the Thai font wouldn't show on excel. Remember your user name and password and then you can print it outside immigration in the copy shop.
Can do Kawthong in Rayong or Andaman Club, a few kms north. Both will give you a 30 day visa exempt stamp. There is a small possibility you will be asked for proof of funds, (10k). Immigration will not let you leave Thailand if they are not prepared to let you back in.
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