Hi, ferry from Marigot is 20 to 25 minutes. Depart tax from Anguilla in Feb was $13pp. The GB Express was definitely quicker and left on time from SXM and Anguiila. Overall timing depends somewhat where you are starting from. In Feb we were in the maho area, so GB was closer to start with.
It's a cash day vs a cc. Parking next door – check with GB, for early Feb we were told not to park there. Obviously must change month to month. Dont forget passports.
J&B