We used to base ourselves in Grenada for hurricane season and often had friends come out to stay. The usual itinerary was people would fly in, meet us at Le Phare Bleu or Prickly Bay first evening. Next morning up the west coast to Carriacou, clear out and straight over to Union to clear in. Then you are right there at Mayreau and the Cays.

So, not a charter but pretty representative of what you want to do.