The Marriage Visa in Thailand also called the “O” Visa or “other” Visa is a Thai Visa for coming to Thailand to visit family or to visit your Thai wife. This visa is valid for 3 months when you enter Thailand. The visa cannot be extended like a tourist visa but can be extended under 2 conditions.
There are types of business visas in Thailand. The first the the most common being the single entry business visa. The second the the multiple entry visa business visa. The first you can normally obtain for a Thai embassy without much issue.