Yep visa options are the same but location in Thailand changes the best location to travel to, the cost and ease of travel and according to that...the application requirements specific to where you will apply. Good luck :)
OK now you are confusing me. There is a visa on arrival that you pay for when you arrive to Thailand and there is a 30 exemption of a visa....This means you have permission to stay in Thailand for 30 days with no visa....Which one do you have..?
Bangkok. OK. NO onward flight is required for a 30 day extension. 100% sure. 1 Photo and TM7 form and copies of passport, Arrival card and entry stamp.