diff --git a/src/components/BookingBreakdown/BookingBreakdown.js b/src/components/BookingBreakdown/BookingBreakdown.js
index 041cbd8a..ddb39deb 100644
--- a/src/components/BookingBreakdown/BookingBreakdown.js
+++ b/src/components/BookingBreakdown/BookingBreakdown.js
@@ -12,7 +12,7 @@ import {
   LINE_ITEM_PROVIDER_COMMISSION,
 } from '../../util/types';
 
-import LineItemUnitPrice from './LineItemUnitPrice';
+import LineItemUnitPriceMaybe from './LineItemUnitPriceMaybe';
 import LineItemBookingPeriod from './LineItemBookingPeriod';
 import LineItemUnitsMaybe from './LineItemUnitsMaybe';
 import LineItemSubTotalMaybe from './LineItemSubTotalMaybe';
@@ -40,7 +40,7 @@ export const BookingBreakdownComponent = props => {
 
   return (
     <div className={classes}>
-      <LineItemUnitPrice transaction={transaction} unitType={unitType} intl={intl} />
+      <LineItemUnitPriceMaybe transaction={transaction} unitType={unitType} intl={intl} />
       <LineItemBookingPeriod transaction={transaction} booking={booking} unitType={unitType} />
       <LineItemUnitsMaybe transaction={transaction} unitType={unitType} />
 
diff --git a/src/components/BookingBreakdown/LineItemBookingPeriod.js b/src/components/BookingBreakdown/LineItemBookingPeriod.js
index 03d49e83..bd018c54 100644
--- a/src/components/BookingBreakdown/LineItemBookingPeriod.js
+++ b/src/components/BookingBreakdown/LineItemBookingPeriod.js
@@ -59,12 +59,8 @@ const LineItemBookingPeriod = props => {
     item => item.code === unitType && !item.reversal
   );
 
-  if (!unitPurchase) {
-    throw new Error(`LineItemBookingPeriod: lineItem (${unitType}) missing`);
-  }
-
   const useQuantityForDayCount = isNightly || isDaily;
-  const count = useQuantityForDayCount ? unitPurchase.quantity.toFixed() : dayCount;
+  const count = useQuantityForDayCount && unitPurchase ? unitPurchase.quantity.toFixed() : dayCount;
 
   const unitCountMessage = (
     <FormattedHTMLMessage
diff --git a/src/components/BookingBreakdown/LineItemSubTotalMaybe.js b/src/components/BookingBreakdown/LineItemSubTotalMaybe.js
index 4dc24e8c..ff30b3bf 100644
--- a/src/components/BookingBreakdown/LineItemSubTotalMaybe.js
+++ b/src/components/BookingBreakdown/LineItemSubTotalMaybe.js
@@ -44,13 +44,9 @@ const LineItemSubTotalMaybe = props => {
     item => item.code === unitType && !item.reversal
   );
 
-  if (!unitPurchase) {
-    throw new Error(`LineItemSubTotalMaybe: lineItem (${unitType}) missing`);
-  }
+  const formattedSubTotal = unitPurchase ? formatMoney(intl, unitPurchase.lineTotal) : null;
 
-  const formattedSubTotal = formatMoney(intl, unitPurchase.lineTotal);
-
-  return showSubTotal ? (
+  return formattedSubTotal && showSubTotal ? (
     <div className={css.lineItem}>
       <span className={css.itemLabel}>
         <FormattedMessage id="BookingBreakdown.subTotal" />
diff --git a/src/components/BookingBreakdown/LineItemUnitPrice.js b/src/components/BookingBreakdown/LineItemUnitPriceMaybe.js
similarity index 78%
rename from src/components/BookingBreakdown/LineItemUnitPrice.js
rename to src/components/BookingBreakdown/LineItemUnitPriceMaybe.js
index 980fd43a..29549016 100644
--- a/src/components/BookingBreakdown/LineItemUnitPrice.js
+++ b/src/components/BookingBreakdown/LineItemUnitPriceMaybe.js
@@ -5,7 +5,7 @@ import { LINE_ITEM_NIGHT, LINE_ITEM_DAY, propTypes } from '../../util/types';
 
 import css from './BookingBreakdown.css';
 
-const LineItemUnitPrice = props => {
+const LineItemUnitPriceMaybe = props => {
   const { transaction, unitType, intl } = props;
   const isNightly = unitType === LINE_ITEM_NIGHT;
   const isDaily = unitType === LINE_ITEM_DAY;
@@ -19,26 +19,22 @@ const LineItemUnitPrice = props => {
     item => item.code === unitType && !item.reversal
   );
 
-  if (!unitPurchase) {
-    throw new Error(`LineItemUnitPrice: lineItem (${unitType}) missing`);
-  }
+  const formattedUnitPrice = unitPurchase ? formatMoney(intl, unitPurchase.unitPrice) : null;
 
-  const formattedUnitPrice = formatMoney(intl, unitPurchase.unitPrice);
-
-  return (
+  return formattedUnitPrice ? (
     <div className={css.lineItem}>
       <span className={css.itemLabel}>
         <FormattedMessage id={translationKey} />
       </span>
       <span className={css.itemValue}>{formattedUnitPrice}</span>
     </div>
-  );
+  ) : null;
 };
 
-LineItemUnitPrice.propTypes = {
+LineItemUnitPriceMaybe.propTypes = {
   transaction: propTypes.transaction.isRequired,
   unitType: propTypes.bookingUnitType.isRequired,
   intl: intlShape.isRequired,
 };
 
-export default LineItemUnitPrice;
+export default LineItemUnitPriceMaybe;
diff --git a/src/util/types.js b/src/util/types.js
index 1e2c2a6b..67f968ae 100644
--- a/src/util/types.js
+++ b/src/util/types.js
@@ -307,6 +307,17 @@ const LINE_ITEMS = [
 
 propTypes.bookingUnitType = oneOf([LINE_ITEM_NIGHT, LINE_ITEM_DAY, LINE_ITEM_UNITS]);
 
+const requiredLineItemPropType = (props, propName, componentName) => {
+  const prop = props[propName];
+
+  if (!prop || prop === '') {
+    return new Error(`Missing line item code prop from ${componentName}.`);
+  }
+  if (!/^line-item\/.+/.test(prop)) {
+    return new Error(`Invalid line item code value ${prop} passed to ${componentName}.`);
+  }
+};
+
 // Denormalised transaction object
 propTypes.transaction = shape({
   id: propTypes.uuid.isRequired,
@@ -323,7 +334,7 @@ propTypes.transaction = shape({
 
     lineItems: arrayOf(
       shape({
-        code: oneOf(LINE_ITEMS).isRequired,
+        code: requiredLineItemPropType,
         includeFor: arrayOf(oneOf(['customer', 'provider'])).isRequired,
         quantity: instanceOf(Decimal),
         unitPrice: propTypes.money.isRequired,