Final answer:
A context diagram for the estate agency would depict the system at the center, with inputs from property owners and potential buyers, processing of the property-buyer match, and outputs like property details, invoices, and reminders.
Step-by-step explanation:
The context diagram for the estate agency in the case study should capture the main inputs, processing, and outputs of the system. At the heart of the diagram, we would represent the estate agency system. The inputs would include the details of properties from the clients and the requirements from potential buyers. The processing involves matching buyer's requirements with available properties and managing transactions. Outputs include details sent to potential buyers, invoices sent to clients, and reminders for unsettled accounts. The diagram would not include internal processes like filing cards but would focus on the interaction between the agency and external entities like clients and buyers. Additionally, the concept of Escrow is particularly relevant when discussing real estate transactions as it provides a means of ensuring that all parties fulfil their obligations, while transferring property taxes and home insurance payments efficiently.