diff --git a/.gitignore b/.gitignore
index 77de841..304c492 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,5 +3,4 @@
 __pycache__/
 
 pay.conf
-log.txt
-test.py
\ No newline at end of file
+log.txt
\ No newline at end of file
diff --git a/README.md b/README.md
index 1b50cf3..6dae6b9 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ Currently handles very basic features, such as:
 
 #### 1. Adding of products
 ```shell script
-http --json http://[::]:5000/product/add email=your_email_here password=your_password_here specs:=@ipv6-only-vm.json
+http --json http://[::]:5000/product/add username=your_username_here password=your_password_here specs:=@ipv6-only-vm.json
 ```
 
 #### 2. Listing of products
@@ -24,20 +24,26 @@ http --json http://[::]:5000/product/add email=your_email_here password=your_pas
 http --json http://[::]:5000/product/list
 ```
 
-#### 3. Ordering products
+#### 3. Registering user's payment method (credit card for now using Stripe)
+
 ```shell script
-http --json http://[::]:5000/product/order email=your_email_here password=your_password_here product_id=5332cb89453d495381e2b2167f32c842 cpu=1 ram=1gb os-disk-space=10gb os=alpine
+http --json http://[::]:5000/user/register_payment card_number=4111111111111111 cvc=123 expiry_year=2020 expiry_month=8 card_holder_name="The test user" username=your_username_here password=your_password_here line1="your_billing_address" city="your_city" country="your_country"
 ```
 
-#### 4. Listing users orders
+#### 4. Ordering products
+
+First of all, user have to buy the membership first.
 
 ```shell script
-http --json GET http://[::]:5000/order/list email=your_email_here password=your_password_here
+http --json http://[::]:5000/product/order username=your_username_here password=your_password_here product_id=membership pay=True
 ```
 
+```shell script
+http --json http://[::]:5000/product/order username=your_username_here password=your_password_here product_id=ipv6-only-vm cpu=1 ram=1 os-disk-space=10 os=alpine pay=True
+```
 
-#### 5. Registering user's payment method (credit card for now using Stripe)
+#### 5. Listing users orders
 
 ```shell script
-http --json http://[::]:5000/user/register_payment card_number=4111111111111111 cvc=123 expiry_year=2020 expiry_month=8 card_holder_name="The test user" email=your_email_here password=your_password_here
-```
\ No newline at end of file
+http --json POST http://[::]:5000/order/list username=your_username_here password=your_password_here
+```
diff --git a/config.py b/config.py
index b951830..4d5e16a 100644
--- a/config.py
+++ b/config.py
@@ -1,11 +1,28 @@
 import configparser
+import sys
+import os
+
 from etcd_wrapper import EtcdWrapper
 from ldap_manager import LdapManager
 
+config_file = os.environ.get('meow-pay-config-file', default='pay.conf')
+
 config = configparser.ConfigParser()
-config.read('pay.conf')
 
-etcd_client = EtcdWrapper(host=config['etcd']['host'], port=config['etcd']['port'])
+try:
+    successfully_read_files = config.read(config_file)
+except configparser.Error as err:
+    sys.exit(err)
 
-ldap_manager = LdapManager(server=config['ldap']['server'], admin_dn=config['ldap']['admin_dn'],
-                           admin_password=config['ldap']['admin_password'])
\ No newline at end of file
+if not successfully_read_files:
+    sys.exit(f'Config file {config_file} couldn\'t be read.')
+
+try:
+    etcd_client = EtcdWrapper(host=config.get('etcd', 'host'), port=config.get('etcd', 'port'))
+
+    ldap_manager = LdapManager(
+        server=config.get('ldap', 'server'), admin_dn=config.get('ldap', 'admin_dn'),
+        admin_password=config.get('ldap', 'admin_password')
+    )
+except configparser.Error as err:
+    sys.exit(f'{err} in config file {config_file}.')
diff --git a/ldap_manager.py b/ldap_manager.py
index 382afab..c0a793f 100644
--- a/ldap_manager.py
+++ b/ldap_manager.py
@@ -1,14 +1,22 @@
 import hashlib
 import random
 import base64
+import sys
 
 from ldap3 import Server, Connection, ObjectDef, Reader, ALL
+from ldap3.core import exceptions
+
+SALT_BYTES = 15
 
 
 class LdapManager:
     def __init__(self, server, admin_dn, admin_password):
         self.server = Server(server, get_info=ALL)
-        self.conn = Connection(server, admin_dn, admin_password, auto_bind=True)
+        try:
+            self.conn = Connection(server, admin_dn, admin_password, auto_bind=True)
+        except exceptions.LDAPException as err:
+            sys.exit(f'LDAP Error: {err}')
+
         self.person_obj_def = ObjectDef('inetOrgPerson', self.conn)
 
     def get(self, query=None, search_base='dc=ungleich,dc=ch'):
@@ -57,7 +65,6 @@ class LdapManager:
         which can be used as LDAP value, e.g. after armoring it once more using
         base64 or decoding it to unicode from ``ascii``.
         """
-        SALT_BYTES = 15
 
         sha1 = hashlib.sha1()
         salt = random.SystemRandom().getrandbits(SALT_BYTES * 8).to_bytes(SALT_BYTES, 'little')
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..843641e
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,4 @@
+ldap3
+etcd3
+stripe
+flask
diff --git a/sample-pay.conf b/sample-pay.conf
index bed5dbe..7138838 100644
--- a/sample-pay.conf
+++ b/sample-pay.conf
@@ -12,8 +12,3 @@ port = 5000
 server = ldap_server_url
 admin_dn = ldap_admin_dn
 admin_password = ldap_admin_password
-customer_dn = ldap_customer_dn
-user_dn = ldap_user_dn
-
-internal_user_ou = users
-customer_ou = customer
\ No newline at end of file
diff --git a/schemas.py b/schemas.py
index 106b591..25555f9 100644
--- a/schemas.py
+++ b/schemas.py
@@ -3,11 +3,9 @@ import config
 import json
 import math
 
-from config import ldap_manager
+from config import ldap_manager, etcd_client
 from helper import resolve_product
 
-etcd_client = config.etcd_client
-
 
 class ValidationException(Exception):
     """Validation Error"""
@@ -105,7 +103,7 @@ class AddProductSchema(BaseSchema):
         user = self.objects['user']
         user = json.loads(user.entry_to_json())
         uid, ou, *dc = user['dn'].replace('ou=', '').replace('dc=', '').replace('uid=', '').split(',')
-        if ou != config.config['ldap']['internal_user_ou']:
+        if ou != config.config.get('ldap', 'internal_user_ou', fallback='users'):
             raise ValidationException('You do not have access to create product.')
 
         product = resolve_product(self.specs.value['usable-id'], etcd_client)
diff --git a/stripe_utils.py b/stripe_utils.py
index 9474f74..1004b86 100644
--- a/stripe_utils.py
+++ b/stripe_utils.py
@@ -1,12 +1,16 @@
-import json
 import re
 import stripe
 import stripe.error
 import logging
+import sys
 
-from config import etcd_client as client, config as config
+from configparser import Error as ConfigParserError
+from config import etcd_client as client, config as config, config_file
 
-stripe.api_key = config['stripe']['private_key']
+try:
+    stripe.api_key = config.get('stripe', 'private_key')
+except ConfigParserError as err:
+    sys.exit(f'{err} in config file {config_file}')
 
 
 def handle_stripe_error(f):
@@ -291,7 +295,7 @@ class StripeUtils(object):
         returns the new object.
 
         :param amount: The amount in CHF cents
-        :param name: The name of the Stripe plan to be created.
+        :param product_name: The name of the Stripe plan (product) to be created.
         :param stripe_plan_id: The id of the Stripe plan to be
                created. Use get_stripe_plan_id_string function to
                obtain the name of the plan to be created
diff --git a/ucloud_pay.py b/ucloud_pay.py
index 09c5813..fc45951 100644
--- a/ucloud_pay.py
+++ b/ucloud_pay.py
@@ -5,7 +5,7 @@ from uuid import uuid4
 
 from flask import Flask, request
 from flask_restful import Resource, Api
-
+from werkzeug.exceptions import HTTPException
 from config import etcd_client as client, config as config
 from stripe_utils import StripeUtils
 from schemas import (
@@ -322,4 +322,15 @@ if __name__ == '__main__':
     api.add_resource(UserRegisterPayment, '/user/register_payment')
     api.add_resource(OrderList, '/order/list')
 
-    app.run(host='::', port=config['app']['port'], debug=True)
+    app.run(host='::', port=config.get('app', 'port', fallback=5000), debug=True)
+
+
+    @app.errorhandler(Exception)
+    def handle_exception(e):
+        app.logger.error(e)
+        # pass through HTTP errors
+        if isinstance(e, HTTPException):
+            return e
+
+        # now you're handling non-HTTP exceptions only
+        return {'message': 'Server Error'}, 500