Sketch the ER diagram for a real estate management system that

controls information about customers, properties and the sell and

buy procedures that are done in the company.

$$Each property has a registration number at the ministry that is

dedicated for that property which could be a house or a land. Each

property has an address that contains the street, city and postal

code.

$$For each land we should register the access road, however for a

house we should register number of rooms.

$$Each buying operation will be accompanied with detailed bill that

contains the date of buying the property, the total price to be paid

and the different payments that the customer should pay with the

due date for each payment.

$$Each payment has a number $($payment $1,$ payment $2,$ payment $3,$

etc$)$ and is usually related to a given bill.

$$A customer has a unique SSN with different phone numbers;

however, a phone number can be related to a single customer