1. In Cruises table you have CruisePrice field
I've entered on some cruise details and I've noticed that they have 4 staterooms: Interior, Outside, Balcony, and Deluxe. Each stateroom / each cruise has its own price, and a customer can order one of them.
2. In CruiseHarbor table you need an additional field, let's call it NightNumber, which will be 0 for Destination and Depart, and will be filled in with an integer representing the visit night (1st, 2nd, 3rd, and so on)
3. You need to change the Planning table's name, as it is vague and might mislead. You may name it CruiseDates with these fields: CruiseDateID (PK), CruiseStartDate, and CruiseEndDate. Also, the FK of the Orders table it is not CruiseID (as in the Cruises table you store a generic cruise details), but CruiseDateID (in the CruiseDates table you store a specific cruise details, let's say a cruise to Bahamas, 9 nights starting January 29th, 2011).
DB2 9.7, 10.5 on Windows