I left everything behind: house, car, family, and I applied for my visa in France. I'm now living a peaceful retirement here in Pattaya, and if my visa isn't extended for any reason, I'll either move to a neighboring country or return to France and rent an Airbnb.
It costs around 11,000 baht for a retirement visa, but your application needs to be complete and it's a quick process. I used VisaThailand, a very reliable and competent website; I recommend them.