I believe Schwab would close your account if you told them your address is in Thailand.
Schwab International is very good. But as mentioned you need 25K US dollars or the equivalent in stocks to open an account.
With Schwab international you can use your Thai address and thai phone number
Also getting money from an ATM or wiring money to a Thai bank is free.
You do have to ask to get the ATM card, a separate form to fill out.