What visa do you need to retire and get married in Thailand?

To retire in Thailand, if you are over 50, you can obtain a 90-day Non-Immigrant Type O visa and then apply for a yearly extension of stay based on retirement, contingent upon meeting financial requirements. Alternatively, you can apply for a Non-Immigrant Type O-A visa (Long Stay) from a Thai consulate, which requires a police background check and a medical certificate. The query also touches upon visas necessary for marriage in Thailand but does not provide specific details on that aspect.