We went to Nassua almost two years ago and, after an excursion to Blackbeards Cay, which was wonderful, decided to take a taxi to Atlantis. We still laugh because we asked the driver if the van had air conditioning. He said yes, so we asked him to just take us for a little tour of Nassua and then to drop us off at Atlantis. The van had A/C and blew hot air - no freon. We left that taxi and found one that had COLD A/C - we asked first.
Once we arrived at the hotel, we just looked at a few of the shops inside and went into the casino, then on to the dining area of the hotel. From there we toured the aquarium. It was gorgeous. I cannot remember the cost, but I am sure you could check the Atlantis Hotel on-line for that info. When we came out of the aquarium, we walked the grounds of the resort, which was beautiful and took amazing photos. This was a very relaxing afternoon for us. We then took a taxi back to the ship. I don't remember paying a lot for the taxi, but don't recall exactly how much it was.