public Contact()
 {
     ContactAddress = new Address();
     Relatives = new List<Relative>();
     Appointments = new List<Appointment>();
     Notes = new List<Note>();
 }
 public Customer()
 {
     Contacts = new List<Contact>();
     VisitAdress = new Address();
     PostalAdress = new Address();
     Notes = new List<Note>();
 }
 public Appointment()
 {
     Location = new Address();
     Notes = new Note();
 }