Draw a Data Flow Diagram 0 for the scenario:

Customers wishing to put their property on the market visit the estate agent who will take details of their house, duplex or flat and enter them on a card which is filed according to the suburb, price range and type of property. Potential buyers complete a similar type of card that is filed by buyer name in binder.

Weekly, the estate agent matches the potential buyer requirements with the available properties and sends buyers the details of selected properties. If the buyer decides to buy a property, the buyer informs the real estate agent who retrieves information about the selected property, completes a contract and sends one copy to the buyer, one to the seller and files one in the office. The property is also updated as sold.

The account clerk looks up information in the contract and sends an invoice to the buyer. A copy is filed in the office. On receipt of payment from the buyer, the invoice copy is stamped as paid.