Hi Rusty,

I have the following page walkthrough (in order) for my Merchello checkout:

Basket > Sign In/Register > Billing & Shipping > Review > Payment.

When I just add normal items to the basket, i.e. LineItemType.Product, I can successfully progress right through to the Review stage where I can review the Billing and Delivery addresses entered at the Billing & Shipping page.

However, when I add products along with a LineItem of Type Discount at the Basket stage, the "preparation.GetBillToAddress()" is null at the Review stage. Have you any idea how this could be null just because I add a Discount item? See below my code:

Basket (Add Discount LineItem):

ILineItem moneyOffItem = new ItemCacheLineItem(LineItemType.Discount, lineItemRow.Name, code, 1, 25, null);
basket.Items.Add(moneyOffItem);
basket.Save();

Billing & Shipping:

private void ValidateAndSetShipping()
        {
            //Customer context
            var customerContext = new CustomerContext(UmbracoContext.Current);
            var basket = customerContext.CurrentCustomer.Basket();
            var preparation = customerContext.CurrentCustomer.Basket().SalePreparation();
            IAddress shippingAddressToUse = null;

            //***************************************************//
            //****************** Addresses **********************//
            //***************************************************//
            //Get the Billing Address
            var billingAddress = new Address();
            var deliveryAddress = new Address();

            //Contact details
            billingAddress.Email = txtEmail.Text;
            billingAddress.Phone = txtTelephone.Text;
            deliveryAddress.Email = txtEmail.Text;
            deliveryAddress.Phone = txtTelephone.Text;

            //Append to the existing billing address
            billingAddress.Name = txtFirstNameBilling.Text + " " + txtLastNameBilling.Text;
            billingAddress.Address1 = txtAddress1Billing.Text;
            billingAddress.Address2 = txtAddress2Billing.Text;
            billingAddress.Locality = txtTownCityBilling.Text;
            billingAddress.Region = txtCountyStateProvinceBilling.Text;
            billingAddress.PostalCode = txtPostcodeZipBilling.Text;
            billingAddress.CountryCode = ddlCountryBilling.SelectedValue;

            //if the checkbox is checked then use the billing address details as the delivery
            if (chkDeliverySameAsBilling.Checked)
            {
                //Append to the existing billing address
                deliveryAddress.Name = txtFirstNameBilling.Text + " " + txtLastNameBilling.Text;
                deliveryAddress.Address1 = txtAddress1Billing.Text;
                deliveryAddress.Address2 = txtAddress2Billing.Text;
                deliveryAddress.Locality = txtTownCityBilling.Text;
                deliveryAddress.Region = txtCountyStateProvinceBilling.Text;
                deliveryAddress.PostalCode = txtPostcodeZipBilling.Text;
                deliveryAddress.CountryCode = ddlCountryBilling.SelectedValue;

                //Set the address to use for shipping
                shippingAddressToUse = billingAddress;
            }
            else
            {
                //Append to the existing delivery address                
                deliveryAddress.Name = txtFirstNameDelivery.Text + " " + txtLastNameDelivery.Text;
                deliveryAddress.Address1 = txtAddress1Delivery.Text;
                deliveryAddress.Address2 = txtAddress2Delivery.Text;
                deliveryAddress.Locality = txtTownCityDelivery.Text;
                deliveryAddress.Region = txtCountyStateProvinceDelivery.Text;
                deliveryAddress.PostalCode = txtPostcodeZipDelivery.Text;
                deliveryAddress.CountryCode = ddlCountryDelivery.SelectedValue;

                //Set the address to use for shipping
                shippingAddressToUse = deliveryAddress;
            }

            try
            {
                //Save the Addresses
                preparation.SaveBillToAddress(billingAddress);
                preparation.SaveShipToAddress(deliveryAddress);

                //***************************************************//
                //******************* Shipping **********************//
                //***************************************************//

                //Associate shipment with the basket's line items
                var shipment = basket.PackageBasket(shippingAddressToUse).FirstOrDefault();

                //Clear any previous saved quotes
                basket.SalePreparation().ClearShipmentRateQuotes();

                // get the quote using the "approved shipping method"
                var shipRateQuotes = shipment.ShipmentRateQuotes().ToArray();

                //Get the cheapest rate
                var approvedShipRateQuote = shipRateQuotes.FirstOrDefault();

                //Apply the shipping charge to the basket
                if (approvedShipRateQuote != null)
                {
                    //Add the quote to the dropdown and make its container visible
                    ddlShippingOptions.Items.Clear();
                    ddlShippingOptions.Items.Add(new ListItem(approvedShipRateQuote.ShipMethod.Name + " (£" + approvedShipRateQuote.Rate.ToString("F") + ")"));
                    ddlShippingOptions.Items.Insert(0, new ListItem("(Please select Shipping Method...)", ""));
                    pnlShipping.Visible = true;

                    //Save
                    preparation.SaveShipmentRateQuote(approvedShipRateQuote);
                }
                else
                {
                    //add an error to the log and display an error to the user stating that the shopping detail si incorrect,
                    //please contact admin
                    ltStatus.Text = "<p class='error-message'>There was an error with calculating the shipping. Please contact us through the <a href='/contact'>contact form</a></p>";
                }
            }
            catch (Exception ex)
            {
                Merchello.Core.Services.AuditLogService auditLog = new Merchello.Core.Services.AuditLogService();
                auditLog.CreateAuditLogWithKey("PFB-ERROR:- CheckoutBilling.ascx - " + ex.Message, true, true);
            }
        }

Review:

var customerContext = new CustomerContext(UmbracoContext.Current);
var basket = customerContext.CurrentCustomer.Basket();
var preparation = customerContext.CurrentCustomer.Basket().SalePreparation();
var billingAddress = preparation.GetBillToAddress();

I am using WebForms, Umbraco 7.2.4 and Merchello 1.8.2.

Thanks in advance!