rc.cs

public class Report
{
    public Report()
    {
        this.Sales = new List<Sale>();
    }

    public string Name { get; set; }
    public List<Sale> Sales { get; set; }
}

public class Sale
{
    public Sale()
    {
        this.Items = new List<Item>();
    }

    public int Id { get; set; }
    public List<Item> Items { get; set; }
}

public class Item
{
    public int Qty { get; set; }
    public float Price { get; set; }
    public Product Product { get; set; }
}

public class Product
{
    public string Name { get; set; }
}