What is the most convenient visa option for someone over 50 with 80,000 Baht or who is married to a Thai national?

I wish the OP can figure out which Visa he has to apply for BEFORE he makes his way to Thailand. Please, he ask about a VISA, not for Extension of Stay at local Immigration after he arrived in Thailand with a Visa. I close the commenting before the OP even gets more confused with all these answers

I am an Australian citizen married to a Thai national for 6 years. I persisted with a marriage extension for several years, until I changed to retiirement extension 2 years ago. The main reason for the change was the marriage extension was much more complicated, because my local Nakhon Si Thammarat Immigration had to send all my documents to Hat Yai. The biggest pain in the arse was having to physically take our local village chief to Immigration to certify me! The whole process took about 4 weeks. Alternatively, retirement extension...in and out in an hour, no village chief, fully stamped. So, in my experience, the choice between the 2 types of extension depends on which office is dealing with your application

Marriage visa

Hi Garry I have been on the marriage visa for 4 years I find it no hassle at all mate

I’m married to and thought the extension of stay due to retirement was easier and went that route. I was going to switch when I got married and my local immigration office suggested I stay with what I have (retirement) as it’s less hassle. I can’t work on this one though, but I Don’t want to either. Lol

You apply for the O-A visa in Australia using Aussi Dollars in Aussie Bank equivalent to 800,000 Baht - plus a medical check and Police background check.

Best option is the Non Immigrant O-A visa, this is the first year Multiple Entry and on each entry you get 1 year of stay. If you leave and come back just before the valid until date on the visa you can have almost 2 years out of it. Be aware that after the valid until date on the visa has passed you need a re-entry permit to travel abroad.

My suggestion is to get the Non Immigrant O-A Multi Entry Visa.

Are you inside Thailand, if yes which visa do you have now, if no in which country are you?