Hi,
We asked a variety of brokers for a response on this, Saxo Capital Markets responded with:
Should be fine to open an account from Sint Maarten – sounds very exotic! I can’t see it on our exclusion list anywhere
We offer accounts in several base currencies (18 I believe) so having a USD account is not a problem
If buying GBP denominated stocks/ETFs on a USD account an FX conversion will occur automatically. We will apply a currency conversion fee on open and close.
We also offer subaccounts which can be denominated in a different currency from the main account.
Read our Saxo review here