A Non Immigrant O Visa is very commonly used for Marriage to a Thai woman. It can also be use for 'Retirement' and can be used for Volunteering (but a bit complicated.
The Non Imm O is not the same as a Non Imm O-A. The O-A can only be obtained by applying at a Thai Embassy or Consulate in your Home Country
- 3 to 4 years ago. A shame they did not update their site... I wish Thailand had not down graded Honorary Consuls. They are contractors to the Thai Embassy system barely able to do anything now.
Houston does not have a real Thai Consulate same as LA. Houston only has an Honorary Royal Thai Consul. I doubt that office is even authorized to issue a B Visa
Non Immigrant B (Business & Employment) and O (for Marriage) One Year Multi-Entry Visas required a Border Run every 90 days to be allowed back into Thailand for another 90 Day Stay. Many Expats utilized this Quite Legal Visa method which had been authorized for 15 years or more.