/// <summary>
        /// Create a new child instance of Car Inventory form and display it
        /// </summary>
        private void ClickNewCarList(object sender, EventArgs e)
        {
            // Get the current instance of the CarInventory form or create a new one if not there
            formCarInventory carList = formCarInventory.Instance;

            // Assign it's MDI parent to be the form this event was called in
            carList.MdiParent = this;

            // Dispaly the form and set it as the focus
            carList.Show();
            carList.Focus();
        }
 /// <summary>
 /// When the form is closed release the instance.
 /// </summary>
 private void CarInventoryFormClosed(object sender, FormClosedEventArgs e)
 {
     instance = null;
 }