I have read the requirements and there are no explicit requirements to allow adding new contractors or deleting existing ones. However, the DBAccess interface specifies this functionality.
Have most people provided this funtionality from the GUI?
I was thinking of having add and delete buttons in my main window. The delete button would display a YN dialog asking the user if he wants to delete the currently selected record. The add button would display a dialog with text fields for all pertinent contractor information.