Retirement visa requires age 50 and proof of min bank level of 500k from what I have found in their website.
You can visit Thailand on passport for 60days then pay for extension. I'm under the impression for some visas you have to have constant travel to and from.
Also another hint when they say limit on visit if you don't want to pay extension just leave the country and come back. You DO NOT have to return to the states you just have to leave the country to count