Consider the case of Healthy People Pharmacy. Healthy People Pharmacy is a small town pharmacy that not only sells pharmaceuticals but also sells items ranging from milk to socks. The pharmacy's owner is looking to purchase a software system to help manage their sales and distribution of goods. As is the case with some pharmacies, they even rent some specialty items such as canes and walkers. The owner desires an electronic way to monitor this process and thus has asked for your help in developing such a system. The domain of selling pharmaceuticals is similar to that of the domain of selling common goods, but there is considerably more regulation regarding the sale of medication. The rental policy is such that depending on the type of item being rented, the length of time is adjusted accordingly (daily, weekly, monthly, and yearly). If an item is damaged during the rental process it needs to be replaced and the customer charged.

Your task is to provide the following:
1. A list of test cases for your proposed system.
2. Perform a basic test-driven development phase for your existing iteration.
3 Select a test framework (xUnit) for your respective system.
4 Discuss the role of this framework within the course of your system
5 Select four components and provide unit tests using your framework.