If you have a Thai wife or a Thai husband then you can apply for a Thai “O” visa. With the location of Chiang Mai many decide once they have registered their marriage in Chiang Mai to cross the border into Laos and obtain a Thai marriage visa in Laos.
The Tourist Visa in Thailand is issued by Thai Embassies abroad and allows you to visit Thailand for a period of 2 months. You may stay in Thailand as a tourist for 2 months and then you are able to extend the visa for another 30 days at Thai Immigration in Chiang Mai or Bangkok.
Some opt for a retirement visa. In order to retire in Chiang Mai or retire in Thailand in general you need to be older than 50 years of age. If you are not 50 years old then you can’t apply for a retirement visa in Thailand.