You, as a systems analyst and designer, were asked to develop an automated (Home Rental Application), in which apartments owners can enter information about their personal information like (name, civil number of owner, expire date of owner civil number, owner's mobile number and owners bank account number). Each owner can have more than one home and each home is owned by one owner only. For each home the proposed system should keep track of the following data items governorate, willayt, city, home description, number of bedrooms, number of bathrooms, furnished or not, floor number, total area in meter square, location, rent value per month in OMR, deposit in OMR) etc.,

Customers (tenants) can use the application to search for apartments of their choice so that they can contact the owners for coordinating an appointment for viewing a specific apartment and renting. The application should keep track of the following data about the tenant (name, civil number of tenant, expire date of tenant civil number, mobile number, nationality, passport number, passport issue date, passport expire date). A tenant can rent more than one home, and a home can be rented to more than one tenant in different time periods.

The system should also keep track of rent contract start date, and rent contract end date. When a particular apartment has been rented the apartment owner can delete their apartment listing from the application. The tenant is responsible for transferring the monthly rent value before or at the beginning of each month to the owners bank account number.

b) Write one of the integrity rules (constraints) (business rules) that should be enforced in this application with the suitable customized error message that should appear to end users in case of violating this rule.