yes the account used for immigration purposes is the exception which is why a will is the best route to go. I even have joint accounts listed in my will even though there is only one signature required to access it. You might as well list all of them on a will whether they are sole or joint accounts.
strictly speaking in Thailand you don't need a lawyer to draw up a valid will as long as it's witnessed, but I used one just for the convenience. I just walked into a law office and paid them 10,000 baht and it was all done in a couple of days.
it's not a minefield. It's a no-brainer to draw up a will bequeathing a bank account to someone else. Legally you don't even need a lawyer to do this but I used one just for the convenience.
just go to any law office. I was charged 10,000 baht to draw up a bilingual will in both English and Thai which bequeathed bank accounts. It's a no-brainer.