Is it better to get a re-entry visa at Suvarnabhumi Airport or immigration before my flight?

Just to make sure I understand correctly: You just need to bring your passport and 1200THB in cash for a single re-entry, nothing else? So far I always thought you need to bring all kinds of copies and a pp photo, that's why I never did it.

I'd say it'll be faster at Suvarnabhumi, you should allow about 30 minutes total (in case you're not the only one getting a re-entry at that time)

If you pay 1200 baht you get a single re-entry without needing a photo, copies or the form (the 200 is a 'service fee').

They sell the re-entry in Departure #2 so if you are flying out in Departure #3 tell them when you stamp out you want a re-entry and they'll show you the way to walk over to the other area to get the re-entry permit