I recently married Thai woman and want to take her back to US for visit only with my family. I am here on Retirement Extension and we plan to live in Thailand. 

What do I need to do. I went online to US site as well as Thai sites and can't figure out the answer. Possible K-3 Visa. I don't know. It Seems awful expensive. 

 

A Tourist Visa is what she needs.  Start reading here:

 

https://th.usembassy.gov/visas/nonimmigrant-visas/

 

When she goes for her interview she should take your passport (not a copy!) that shows your Retirement extension(s).  You should also do a SHORT cover letter explaining that you're retired here, living with your wife, in what?  Condo?  House?  Apartment?  How many retirement extensions have you had, note this.

 

The interviewing officer will probably think that if you are going to return after the visit, your wife will most likely return with you.

 

Mac