Hi Dalton! Congratulations on your upcoming cruise! Wish I were going. Grand Cayman beaches are clean, white sand, and free (at least the ones I've been to). You can catch a cab (read mini-bus) at the dock (where the tenders drop you) and they'll take you to 7 mile. They run continuously during the day, so don't worry about not being able to get back. I think it was $6.50/pp. I usually walk a good ways up from where they drop you off, but the whole way there are plenty of bars/restaurants/hotels and places to rent chairs/umbrellas/sea toys. The island has grown since the first time I visited. There were only little shacks on the beach for frozen drinks and only a few hotels, not now. Still they have kept the beach, itself, clean. You won't be hassled by vendors as much, if at all, either. It's a great beach/shopping day. Just be sure to give yourself enough time to get back to the tender area, traffic can get thick depending on how many ships are in port. Bon Voyage
Oops, I forgot, Seven Mile is about 6 miles from the tender area.