Got sick last year and needed urgent surgery at a private hospital in Bangkok but had to pay 800,000 Baht in advance. I had enough funds and after paying, their team of doctors and nurses got ready immediately for a complicated 4-hour operation. No money, no operation. The final bill including hospital accommodation, medication, rehabilitation and everything else was 1,4 million Baht, the 800,000 was only for the operation. Don't even think about retiring in Thailand without sufficient funds.