, of course you can afford to retire without 800k sitting in some Thai bank earning nothing. Just be on the visa that allows you to bring in 65k every month, that is perfectly adequate amount for you to live on as long as you are wise in your spend habits.
Or keep your money at home and bring just what you need and do what i just did, get a new OA visa from your own country every two years, saves all those immigration interpretations.
, yes i would reapply for a visa as i dont need or want to tie the 800k/400k of funds in a Thai bank and i dont need the monthly 65k to live on. I just find it simplier and less bank fees to move enough to live on every quarter.
yes, i think it helps that i have an Australian bank account and can state a friends address as my forwarding address and of course the police clearence and medical is done in Australia. It certainly keeps the cost down flying to Perth to do all that.