I had a marriage visa in Thailand 14 years ago also and it was so much easier then, my wife and I left Thailand in 2012 and we returned back to Thailand this year in june, the visa rules really did change.
I did mine in Udon Thani and the witness had to come to immigration with us and I had a visit from immigration police about 2 days later and then again 30 days after when I went to get my stamp
I am married to a Thai national and we needed a that bank account so I had my wife open 2 but I used one in her name and one she used. Until I had my Thai house book and pink id card.
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