Create a set of use cases for the following high-level requirements in a housing system run by the Campus Housing Service. The Campus Housing Service helps students find apartments. Owners of apartments fill in information forms about the rental units they have available (e.g., location, number of bedrooms, monthly rent), which are entered into a database. Students can search through this database via the Web to find apartments that meet their needs (e.g., a two-bedroom apartment for $800 or less per month within ½ mile of campus). They then contact the apartment owners directly to see the apartment and possibly rent it. Apartment owners call the service to delete their listing when they have rented their apartment(s).

In building the major use cases, follow the four-step process: Identify the use cases, identify the steps within them, identify the elements within the steps, and confirm the use cases.