Just did my 30 day extension in Hua Hin. 20 min in and out. No photos needed. No application. Just my address and phone number on a photocopy of my
Passport. They said they are the only fully computerized IO. And my landlord registered me. I asked about traveling domestically and they said as long as I return to the same address - there is no further need to check back in. SLICK!