If I arrive in BKK on a visa on arrival, 30 days, then go to CW to extend, how long can I extend for, and what are the fees. I am on an Oz passport arriving from Saigon.
TLDR : Answer Summary
If you arrive in Bangkok on a Visa on Arrival for 30 days and wish to extend it at Chaeng Watthana, you can extend for an additional 30 days. The required documents include your passport, copies of the passport's front page and visa stamp, a filled TM7 form, two photos, and the fee of 1,900 Thai baht. No additional TM30 or TM28 forms are needed.