diff --git a/src/layouts/payment-method/add-vaps-modal-buttons/add-vaps-modal-buttons.vue b/src/layouts/payment-method/add-vaps-modal-buttons/add-vaps-modal-buttons.vue
index fa78915c1..d2195c5e5 100644
--- a/src/layouts/payment-method/add-vaps-modal-buttons/add-vaps-modal-buttons.vue
+++ b/src/layouts/payment-method/add-vaps-modal-buttons/add-vaps-modal-buttons.vue
@@ -26,7 +26,7 @@
                 v-if="wipersModal"
                 @footer-button-action="addWipersToCart('WipersModal', wipersModal)"
                 footerButtonActionName="footer-button-action">
-                <div v-if="wipersToDisplay === 'both'" class="wiper-options">
+                <div v-if="wipersToDisplay === wipersToDisplayStrings.BOTH" class="wiper-options">
                     <div>
                         <checkboxQuestion
                             class="mb-5"
@@ -42,10 +42,14 @@
                         <p class="price">+${{ wipersModal.totalRearPrice }}</p>
                     </div>
                 </div>
-                <div v-else-if="wipersToDisplay === 'front'" class="wiper-options">
+                <div
+                    v-else-if="wipersToDisplay === wipersToDisplayStrings.FRONT"
+                    class="wiper-options">
                     <p class="price">+${{ wipersModal.totalFrontPrice }}</p>
                 </div>
-                <div v-else-if="wipersToDisplay === 'rear'" class="wiper-options">
+                <div
+                    v-else-if="wipersToDisplay === wipersToDisplayStrings.REAR"
+                    class="wiper-options">
                     <p class="price">+${{ wipersModal.totalRearPrice }}</p>
                 </div>
             </contentGroupModal>
@@ -139,11 +143,13 @@ export default {
     },
     computed: {
         currentCartItems() {
-            return this.modelValue;
+            const modelValue = this.modelValue;
+            if (!modelValue.vaps) modelValue.vaps = [];
+            return modelValue;
         },
         rainDefenseModal() {
             const lineItem = this.availableLineItems.find((item) => {
-                return item.partType === partTypeStrings.FRONT_WIPER;
+                return item.partType === partTypeStrings.RAIN_DEFENSE;
             });
             if (lineItem)
                 lineItem.listPrice = parseFloat(
@@ -190,7 +196,7 @@ export default {
             if (!this.answersCmsData) return buttons;
 
             const rainDefenseInCart = this.currentCartItems.vaps?.some((vap) => {
-                return vap?.partType === partTypeStrings.FRONT_WIPER;
+                return vap?.partType === partTypeStrings.RAIN_DEFENSE;
             });
             const frontWipersInCart = this.currentCartItems.vaps?.some((vap) => {
                 return vap?.partType?.includes(partTypeStrings.FRONT_WIPER);
@@ -240,6 +246,9 @@ export default {
 
             return buttons;
         },
+        wipersToDisplayStrings() {
+            return wipersToDisplayStrings;
+        },
     },
     components: {
         buttonQuestion,