Report of successful non-immigrant O multiple-entry visa (marriage) in HCMC.
I just returned from HCMC with my brand new visa and it could not have been easier. I submitted a copy of my marriage certificate (with the rose border) signed by both of us, along with a copy of my wife's ID card and tabien baan, both signed by her. She also wrote a simple handwritten letter saying we were legally married and asking could they please give me the visa. She also signed this paper. I also filled out the form they have in the office, with 2 photos (blue background was OK), and 200 USD in cash. The woman behind the counter spent about 30 seconds looking over the docs, then gave me a receipt to use when retrieving my passport the next day. I was concerned that the handwritten letter from my wife should be a certain format, but it was no problem. I spent less than a minute submitting my paperwork, then less than another minute picking up my passport the next day.
We sat in an outdoor restaurant across the street waiting for the consulate to open, and I counted about 25-30 people waiting in line. When I eventually went inside to get my visa, two English-speaking guys were trying to understand why there were only given 30 days instead of 60 (for their tourist visas), but I didn't stick around long enough to hear the answer. Outside, an Englishman asked about my results, then showed me the warning stamp on his tourist visa saying (basically) "this person frequently comes into Thailand on tourist visas". I suspect he will not be able to get another visa at that consulate, and I was left with the distinct impression that this consulate is also starting to crack down.
Also, when going through Passport Control at Suvarnabhumi, I was able to go with my wife through the (much shorter) Thai Passport lanes, saving us lots of time.
Finally, VietJetAir is also starting to crack down on their 7kg per person baggage limit (at least when leaving HCMC), so we were charged and forced to check a bag (note that we did not have this trouble going into or out of Dalat, on the same airline). I highly recommend that you look closely at your baggage weight if you travel this airline through this airport, as they delayed the flight about 30 minutes while they tested everyone's bag and forced lots of people to pay extra.
Hope this helps someone.
TLDR : Answer Summary
The author successfully applied for a non-immigrant O multiple-entry visa at the Thai consulate in Ho Chi Minh City (HCMC) with a straightforward process. They submitted their marriage certificate, wife’s ID and tabien baan, a handwritten letter from their wife, two photos, and paid $200 USD in cash. The application was processed quickly, allowing them to pick up their passport the next day. The author noted an increase in scrutiny at the consulate, particularly towards those frequently entering Thailand on tourist visas. They also mentioned recent baggage weight enforcement by VietJetAir.
