Want to use Data Validation? to give text a value that's used in a formula elsewhere on the sheet

We have a group plaing to charter a sailboat as a vacation for 10 days. I'm trying to show the total costs of the trip. It's a simple spreadsheet listing many semi-fixed costs like food, beer, fuel, insurance, mooring fees, etc. etc. I know that Boat A costs 1000, Boat B costs 1500 and Boat C costs 2000. I want the user to be able to select from a drop down Boat A, B, or C and have it effect the bottom line sum. Currently, using Data Validation all I know how to do is have the values (1000, 1500, 2000) in the dropdown list. I want an end value to change automatically based on what the user picked (Boat A, Boat B, Boat C). Thanks in advance.