diff --git a/services/abonemments/AbonemmentService.js b/services/abonemments/AbonemmentService.js
index dd1c46d..c2e520c 100644
--- a/services/abonemments/AbonemmentService.js
+++ b/services/abonemments/AbonemmentService.js
@@ -7,6 +7,22 @@ const ReferralService = require('../referral/ReferralService');
 const ReferralTokenRepository = require('../../repositories/referral/ReferralTokenRepository');
 const MailService = require('../email/MailService');
 
+const CAPSULES_PER_PACK = 10;
+const MIN_ABO_PACKS = 6;
+const MAX_ABO_PACKS = 10000;
+
+function getPackCountError(totalPacks) {
+  if (totalPacks < MIN_ABO_PACKS) {
+    return `Order must contain at least ${MIN_ABO_PACKS} packs (${MIN_ABO_PACKS * CAPSULES_PER_PACK} capsules).`;
+  }
+
+  if (totalPacks > MAX_ABO_PACKS) {
+    return `Order cannot contain more than ${MAX_ABO_PACKS} packs (${MAX_ABO_PACKS * CAPSULES_PER_PACK} capsules).`;
+  }
+
+  return null;
+}
+
 class AbonemmentService {
   constructor() {
     this.repo = new AbonemmentRepository();
@@ -40,7 +56,7 @@ class AbonemmentService {
     return typeof email === 'string' ? email.trim().toLowerCase() : null;
   }
 
-  // NEW: single bundle subscribe using items array (12 packs, 120 capsules)
+  // NEW: single bundle subscribe using items array (pack-based order content)
   async subscribeOrder({
     items,
     billingInterval,
@@ -114,7 +130,7 @@ class AbonemmentService {
       const coffeeId = item?.coffeeId;
       const packs = Number(item?.quantity ?? 0);
       if (!coffeeId) throw new Error('coffeeId is required for each item');
-      if (!Number.isFinite(packs) || packs <= 0) throw new Error('quantity must be a positive integer per item');
+      if (!Number.isInteger(packs) || packs <= 0) throw new Error('quantity must be a positive integer per item');
 
       const product = await this.getCoffeeProduct(coffeeId);
       if (!product || !product.is_active) throw new Error(`Product ${coffeeId} not available`);
@@ -134,6 +150,9 @@ class AbonemmentService {
       });
     }
 
+    const packCountError = getPackCountError(totalPacks);
+    if (packCountError) throw new Error(packCountError);
+
     const now = new Date();
     const nextBilling = this.addInterval(now, billingInterval || 'month', intervalCount || 1);
 
@@ -590,7 +609,7 @@ class AbonemmentService {
       const coffeeId = item?.coffeeId;
       const packs = Number(item?.quantity ?? 0);
       if (!coffeeId) throw new Error('coffeeId is required for each item');
-      if (!Number.isFinite(packs) || packs <= 0) {
+      if (!Number.isInteger(packs) || packs <= 0) {
         throw new Error('quantity must be a positive integer per item');
       }
 
@@ -611,9 +630,8 @@ class AbonemmentService {
       });
     }
 
-    if (totalPacks !== 6 && totalPacks !== 12) {
-      throw new Error('Order must contain exactly 6 packs (60 capsules) or 12 packs (120 capsules).');
-    }
+    const packCountError = getPackCountError(totalPacks);
+    if (packCountError) throw new Error(packCountError);
 
     const previousPacks = Array.isArray(abon.pack_breakdown)
       ? abon.pack_breakdown.reduce((sum, item) => sum + Number(item?.packs || item?.quantity || 0), 0)