I see what you guys are talking about now.. The 'Am I eligible' question. Its weird that is not part of the application process. I just ignored it.
Also, noteworthy.. when I select that I am a US passport holder and I select
Denmark, Canada, Bahamas, it says that I am eligible. There are probably some others as well.
Like said, the 'eligible' question isn't part of the application process. The application ask about nation of origin (birth nation) and current residence.
I want to HCMC (Saigon) a few years ago. I don't recall if they asked for all documents but its a good idea to bring them. I do remember that they only accept USD and the bills have to be in mint condition. Both drop-off and pick-up was quick and painless.
Oddly I just did this. I don't recall it asking my current location but it did ask me about my country of residence and my nationality. Legally both are USA.
I have found the Pattaya immigration office to be quite unpredictable. One time they wouldn't allow me to extend until the day before it expired.. In that case I had to use an agent.
You can likely extend at any immigration office so long as you have a hotel room booked in their district when you apply for the extension.
You can get a long term visa for: being wealthy, having high-demand skill set, get married, adopt a kid, get old, or get a job. Each option has it's own set of complications and requirements. There is also a medical visa but that may be limited to the time for treatment.
I have been questioned a couple of times coming into Thailand. What is more strange is that I usually don't get questioned. I have a long questionable visa history but they let me. I am almost always dressed like a bum but I am always very polite.
You're always taking a risk coming to Thailand on back-to-back tourist visas (or similar). It's best to have a plan B and not need it then to need a plan B and not have it.
I crossed that border a long time ago... Just border bounce, I was on the Lao said of border for 30 minutes.
I don't recall if they ask for more documents or not.. They probably did. The immigration officer sent me the supervisor who then had a stern conversation with me.. She was actually a nice lady. In the end she said "... next time... when come back...", point being they're pretty cool up there but its a good idea to travel with all the things you need.. No reason to cause yourself a head ache.
I think many people choose a language school that will handle the paperwork for them. In that case, you would contact the school and ask which visa type you need. When I was doing a working visa they could convert some visa types but not others. I would contact the school and ask them.
If all you want to do is stay in Thailand for 6 months a multiple entry tourist visa, or even single entry tourist visa. Taking the day to do a border run is preferable to taking a couple of days to get the paperwork for non-o visa.