using System;

using System.Reflection;

public class Program

{

    public static void Main()

    {

        Entity newEntity = new Entity();

        Type entityType = typeof(Entity);

        PropertyInfo entityPropInfo = entityType.GetProperty("Address");

        Type addressType = entityPropInfo.PropertyType;

        PropertyInfo addressPropInfo = addressType.GetProperty("AddressLine1");

        var instance = Activator.CreateInstance(addressType);

        Console.WriteLine(instance);

        addressPropInfo.SetValue(instance, "test");

        Console.WriteLine(instance.ToString());

    }

}

​

public class Entity

{

    public string Name { get; set; }

    public Address Address { get; set; }

}

​

public class Address

{

    public string AddressLine1 { get; set; }    

}