public StandardFormBookingModel(Booking booking)
     : base(booking)
 {
     ContactId = booking.MainContactId;
     PhoneNumber = booking.MainContact.PhoneNumber;
     MainContactName = booking.MainContact.MainContactName;
     BandName = booking.MainContact.Name;
     EmailAddress = booking.MainContact.EmailAddress;
     if (booking.Product.Type == Product.ProductType.CanPickFrom)
         Room = booking.Rooms.FirstOrDefault().Id;
     RateId = booking.Rate == null ? null : booking.Rate.Id;
     RateDescription = booking.Rate == null ? null : booking.Rate.Description;
     RatesToPickFromMaybe = booking.Rate == null
                                ? new List<Rate>()
                                : booking.Rooms.FirstOrDefault().Rates.ToList();
     OneOffCharge = booking.OneOffCharge;
     AdditionalEquipmentAndNumberRequired = booking.FlattenAdditionalEquipment();
 }