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..0c7976ea8 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);
@@ -209,17 +215,17 @@ export default {
             if (!rainDefenseInCart) {
                 // NO RAIN DEFENSE IN CART; SHOW RAIN DEFENSE BUTTON
                 const modalData = getAnswer("RainDefenseModal", this.answersCmsData);
-                modalData.SubText = "+$" + this.rainDefenseModal.listPrice;
+                modalData.SubText = "+$" + this.rainDefenseModal?.listPrice;
                 buttons.push(modalData);
             }
 
             const modalData = getAnswer("WipersModal", this.answersCmsData);
             if (!frontWipersInCart) {
-                if (!rearWipersInCart && this.wipersModal.rearWiperLineItems.length > 0) {
+                if (!rearWipersInCart && this.wipersModal?.rearWiperLineItems.length > 0) {
                     // NO REAR WIPERS or FRONT WIPERS IN CART; SHOW COMBO BUTTON
                     const prices = [
-                        this.wipersModal.totalFrontPrice,
-                        this.wipersModal.totalRearPrice,
+                        this.wipersModal?.totalFrontPrice,
+                        this.wipersModal?.totalRearPrice,
                     ];
                     prices.sort((a, b) => a - b);
                     modalData.SubText = "+$" + prices[0] + " - $" + prices[prices.length - 1];
@@ -227,19 +233,22 @@ export default {
                     buttons.push(modalData);
                 } else {
                     // NO FRONT WIPERS IN CART; SHOW ONLY FRONT WIPERS BUTTON
-                    modalData.SubText = "+$" + this.wipersModal.totalFrontPrice;
+                    modalData.SubText = "+$" + this.wipersModal?.totalFrontPrice;
                     this.updateWipersToDisplay(wipersToDisplayStrings.FRONT);
                     buttons.push(modalData);
                 }
-            } else if (!rearWipersInCart && this.wipersModal.rearWiperLineItems.length > 0) {
+            } else if (!rearWipersInCart && this.wipersModal?.rearWiperLineItems.length > 0) {
                 // NO REAR WIPERS IN CART; SHOW ONLY REAR WIPERS BUTTON
-                modalData.SubText = "+$" + this.wipersModal.totalRearPrice;
+                modalData.SubText = "+$" + this.wipersModal?.totalRearPrice;
                 this.updateWipersToDisplay(wipersToDisplayStrings.REAR);
                 buttons.push(modalData);
             }
 
             return buttons;
         },
+        wipersToDisplayStrings() {
+            return wipersToDisplayStrings;
+        },
     },
     components: {
         buttonQuestion,