Boat Ticket
The Boat Ticket (ふねのチケット, Fune no chiketto?, lit. Boat Ticket) is a Quest item in Golden Sun that is specifically needed to board the Tolbi-bound Ship at Kalay Docks. The party merely enters the one building at the dock, talks to the receptionist, and pays 600 coins for the item (apparently this one item represents four boat tickets in one, since the fare is 150 coins per person and Isaac's group is comprised of four).
At the docks, talking to and mind-reading the people there implies that normally, the tickets are much cheaper. However, in order to take advantage of the fact that people are dependent on the ships to get to Tolbi (the road people could take counterclockwise above the Karagol Sea has been blocked off by a landslide just north of the docks, and it is currently the season of the Colosso tournament at Tolbi), the captain of the ferry has apparently increased the prices.