I use a Medicare advantage plan. I pay the hospital bill for the Thai hospital that provided the care and then submit to Medicare for reimbursement. Every submitted claim has been paid to me. This only works if you live outside the US for less than 6 months a year.
Don’t listen to the negative comments. I married a Thai woman 35, no 36 years ago. We live half the year in Thailand and the other half in another country.
You don’t need it approved before you fly. You could arrive and enter on the visa waiver. Then when your visa is approved, do a quick border run. You don’t need to stay outside Thailand overnight because the purpose of the border run is to activate your DTV visa.
Sounds good. Plenty of obstacles along the way. My Thai wife and I considered opening a restaurant in our village, but we can see she would earn maybe 500 to 1,000 THB a day after expenses and a 10 hour day. We had a Thai restaurant in North America and we each earned $300 - $500 USD (10,000 - 17,000 THB) per day. We earned a good retirement nest egg and are not even considering working for peanuts in Thailand.