Good points... As we all know, there is always a small possibility of meeting the Official that is on the take, but aside from that very slim chance, just giving attention to Thai etiquette in a country where Form often superseeds Substance will go a very long way to make things go smoothly.
You can go to a Thai Immigration office and get a <7 day extension> for 1900 Bahts. If you can share what Visa you have would help greatly so we can assist you further.
Interesting point of view indeed. Not necessarily having to speak Thai, but the recommendation is more directed at showing respect and being mindful of Thai etiquette protocols that are the laws of the land we are trying to enter. Keeping in mind that Form supersedes Substance here in Asia, just following a few simple steps in Asian protocol will greatly improve the chances of having a positive experience. By reading endless amounts of posts, I think most are very well aware that rules seem to just pop up or be made up on a whim, but if one takes a moment to reflect on how the interaction actually took place from a <Thai way> point of view, that might actually help to find out where things actually went wrong. For those more fortunate ones who have had the benefit of sharing a few cold ones with some well educated and well travelled Thai's will know that we foreigners are often seen as over bearing and unpolished in our ways of enteracting, all adding up to being very impolite (=Mai Greng Jai) which in addition to breaking one the principles of the Buddhist commandments, is also considered a significant mistake in Thai etiquette. Then, if we put this concept in a context of an enteraction with a Border Patrol Officer, I think everyone can see the potential for a good thing to go sideways very quickly. This even if one has all is paperwork ducks in a row. Not trying to start a major debate here, but just trying to point out a few details to help the OP get success.
I totally here and appreciate what the agent said and how definite he might of made it sound, but as I am sure we can all agree, they seem to make the rules as they go here, but we tend to forget that Form is much more important than Substance in this country where politeness is not only a virtue, but a must. To give you an idea, I was asked the exact same thing at the exact same border and then slowly took out my folder with the Sign and Bank Stamped proof of funds letter and handed it over ever so gingerly, in the same manner we are treated with the transfer of cash at decent restaurants (one hand behind the other), along with a polite smile and the Border Patrol gladly accepted it. Good to note that if we take a moment to think that we are a guest here and Not make anyone lose face or feel uncomfortable <Mai Greng Jai> here in the Land of Smiles, everything will go smoothly. Hope this helps
If you have the 3 proof requirements they request, everything should go smoothly. However, the one thing I learned the hard way is to never forget the ultimate importance of Thai Etiquette when engaging in any exchange with Thai poeple, especially when dealing with the Authorities. First walking slowly and being calm is a good practice, with the must-have Smile of Politeness to establish a <Greng Jai> exchange is a good habit to pick up. Then, if you are comfortable with Thai Language, maybe throw in a small <Sawasdee khrap> while smiling BEFORE engaging in any conversation will go a long way to help set a pleasing <Greng Jai> atmosphere. This second recommendation will also help show your level of ultimate respect for Thai culture and this small but VERY meaningful gesture should definitely earn you that same respect in return. When addressing anyone of authority, it is considered amongst Thai's to be of utmost importance to address the Officer with the proper <Wai> gesture accompanied with the standard polite Smile prior to engaging in any conversation. Eventhough I lived here for many years, I have been guilty of forgetting these steps on occasion and can honestly say that when in the Land Of Smiles, it is definitely worth making 100% sure to both know and follow these rules of etiquette that are seldom mentioned. Lastly, it goes without saying that when we are seeking to be treated professionally, dressing appropriately for this professional occasion would be highly recommended. Hopefully this will help to make your Visa run go smoothly and in case anyone is curious, I included the 3 different <Wai> greetings and how to use them. Shoke dee took khun na khrap