Как сделать привязку DataGridView к ComboBox?

Есть datagridview и combobox их источники List-ы, мне нужно чтобы когда выбирали один элемент из combobox, то datagridview показывал элементы связанные с элементом из combobox. Чтобы вы понимали, есть два класса один хранит данные другого. И еще мне нужна возможность выбирать элемент из combobox и добавлять туда новые элементы. Очень нужна ваша помощь.

Program.cs

  {  using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Threading.Tasks;
  using System.Windows.Forms;
namespace Ex1
{
    public class Client
    {
    public string Name { get { return name; } set { name = value; } }
    public string Birth { get { return birth; } set { birth = value; } }
    public string Country { get { return country; } set { country = value; } 
   }
        public string NOP { get { return nop; } set { nop = value; } }
    public string PID { get { return pid; } set { pid = value; } }
    public string Date { get { return date; } set { date = value; } }
    //public int NoR { get { return nor; } set { nor = value; } }
    public Rooms Room { get { return room; } set { room = value; } }
    private string name;
    private string birth;
    private string country;
    private string nop;
    private string pid;
    private string date;
    private Rooms room;
  //  private int nor;
   }
    public class Hotel
    {
        public string CName { get { return cname; } set { cname = value; } }
    public string CompanyOwner { get { return cowner; } set { cowner = 
value; } }
        public string NumStars { get { return numstar; } set { numstar= 
value; } }
    public string NumRooms { get { return numrooms; } set { numrooms = value; } }
    public List<Client> Clients { get { return clients; } set { clients = 
value; } }
        public string LRooms { get { return lrooms; } set { lrooms = value; 
} }
        private string cname;
       private string cowner;
         private string numstar;
         private string lrooms;
         private string numrooms;
         private List<Client> clients;
         public Hotel()
         {
             clients = new List<Client>();
         }
     }
     public class Rooms
     {
         public int NumberORoom { get { return nor; } set { nor = value; } }
         private int nor;
     }
     static class Program
     {
         /// <summary>
         /// The main entry point for the application.
         /// </summary>
         [STAThread]
         static void Main()
              {
             Application.EnableVisualStyles();
             Application.SetCompatibleTextRenderingDefault(false);
             Application.Run(new Form1());
              }
          }
      }
 }

Form1.cs

 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
 using System.Drawing;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using System.Windows.Forms;
 using System.IO;
 namespace Ex1
 {
     public partial class Form1 : Form
     {
         public BindingList<Hotel> hotels = new BindingList<Hotel>();
         // public System.Windows.Forms.ComboBox HotelsComboBox;
         private BindingList<Client> clients = new BindingList<Client>();

         private Client Klient { get; set; }
         public Form1()
         {
             InitializeComponent();
             Klient = null;
         }
         private Hotel NHotel { get; set; }
         private void backgroundWorker1_DoWork(object sender,                     
    DoWorkEventArgs e)
        {
        }
        private void comboBox1_SelectedIndexChanged(object sender, EventArgs         
e)    
        {
        }
        private void domainUpDown1_SelectedItemChanged(object sender,         
EventArgs e)
        {
        }
        private void CNameBox_TextChanged(object sender, EventArgs e)
        {
            //string CNB = CNameBox.Text;
        }
        private void CBirthBox_TextChanged(object sender, EventArgs e)
        {
            //string CBB = CBirthBox.Text;
        }
        private void CCountryBox_TextChanged(object sender, EventArgs e)
        {
           //string CCB = CCountryBox.Text;
        }
        private void CRentersBox_TextChanged(object sender, EventArgs e)
        {
        //string CRB = CRentersBox.Text;
        }
        private void CPassIdBox_TextChanged(object sender, EventArgs e)
        {
       // string CPIDB = CPassIdBox.Text;
        }
        private void label6_Click(object sender, EventArgs e)
        {
        }
        private void CDateBox_TextChanged(object sender, EventArgs e)
        {
        //string CDB = CDateBox.Text;
        }
        private void ClientAddBtn_Click(object sender, EventArgs e)
        {
             if (CNameBox.Text == String.Empty || CBirthBox.Text ==     
 String.Empty || CCountryBox.Text == String.Empty || CRentersBox.Text ==              
String.Empty || CPassIdBox.Text == String.Empty || CDateBox.Text ==                
String.Empty)
        {
            MessageBox.Show("Please fill all information about client");
        }
         else
        {
            string CNB = CNameBox.Text;
            string CBB = CBirthBox.Text;
            string CCB = CCountryBox.Text;
            string CRB = CRentersBox.Text;
            string CPIDB = CPassIdBox.Text;
            string CDB = CDateBox.Text;
            string CRNB = RoomNumberBox.Text;

            Klient = new Client() { Name = CNB, Birth = CBB, Country = CCB, 
Date = CDB, PID = CPIDB, NOP = CRB };
                MessageBox.Show("Adding Client was succsessfull!");
                clients.Add(Klient);

            dataGridView1.DataSource = clients;
            // dataGridView1.Rows.Add(CNameBox.Text, CBirthBox.Text, 
      CCountryBox.Text, CRentersBox.Text, CPassIdBox.Text, 
      RoomNumberBox.Text);
            dataGridView1.Refresh();
        }
    }
    private void Form1_Load(object sender, EventArgs e)
    {
    }

    private void RoomNumberBox_TextChanged(object sender, EventArgs e)
    {
       //string CRNB = RoomNumberBox.Text;
    }
    private void dataGridView1_CellContentClick(object sender, 
    DataGridViewCellEventArgs e)
    {
    }
    private void HotelsComboBox_SelectedIndexChanged(object sender, 
    EventArgs e)
    {
        HotelsComboBox.DataSource = hotels;
    }
    private void dataGridView1_CellContentClick_1(object sender, 
    DataGridViewCellEventArgs e)
    {
    }
    private void LivingRoomBox_TextChanged(object sender, EventArgs e)
    {
    }
    private void HNameBox_TextChanged(object sender, EventArgs e)
    {
    }
    private void button1_Click(object sender, EventArgs e)
    {
        if (HNameBox.Text == String.Empty || COwnerBox.Text == String.Empty 
    || NumberStars.Text == String.Empty || NumRoomsBox.Text == String.Empty 
    || LivingRoomBox.Text == String.Empty)
        {
            MessageBox.Show("Заполните пожалуйста все поля");
        }
        else
        {
            NHotel = new Hotel() { CName = HNameBox.Text, CompanyOwner = 
   COwnerBox.Text, NumStars = NumberStars.Text, NumRooms = NumRoomsBox.Text 
   , LRooms= LivingRoomBox.Text };
            hotels.Add(NHotel);
            MessageBox.Show("Adding was successfull!");
            HotelsComboBox.DataSource = hotels;
        }
       }
    private void NumStars_TextChanged(object sender, EventArgs e)
    {
    }
    private void NumberStars_TextChanged(object sender, EventArgs e)
    {
    }
   }
  }
введите сюда код