Our questions are
1) whether car renting is better or is using taxis for all or parts of our trip.
2) Are there car rentals at the PDC (Playa del Carmen) ferry dock or other places?
Our family of 4 includes two girls, ages 4 & 7.
On Day 2, we'd like to spend all day at XCaret.
On Day 3, check out & go to Merida.