diff --git a/killbill/__init__.py b/killbill/__init__.py
index c0804a4..a93370a 100644
--- a/killbill/__init__.py
+++ b/killbill/__init__.py
@@ -16,6 +16,7 @@
 # under the License.
 #
 
+user = 'KillBill Python Client'
 base_uri = 'http://localhost:8080'
 username = 'admin'
 password = 'password'
@@ -39,4 +40,10 @@
 
 from killbill.resource import Resource
 from killbill.account import Account
+from killbill.bundle import Bundle
+from killbill.catalog import Catalog
+from killbill.custom_field import CustomField
+from killbill.invoice import Invoice
+from killbill.payment_method import PaymentMethod
+from killbill.plan_detail import PlanDetail
 from killbill.subscription import Subscription
diff --git a/killbill/account.py b/killbill/account.py
index fdfbe9c..030b7b1 100644
--- a/killbill/account.py
+++ b/killbill/account.py
@@ -24,7 +24,7 @@ class Account(killbill.Resource):
     def __init__(self, **d):
         super(Account, self).__init__(d)
 
-    def create(self, user, reason=None, comment=None, **options):
+    def create(self, user=killbill.user, reason=None, comment=None, **options):
         created_account = self.post(self.KILLBILL_API_ACCOUNTS_PREFIX,
                                     self.to_json(),
                                     {},
@@ -36,12 +36,20 @@ def create(self, user, reason=None, comment=None, **options):
                                     ))
         return self.refresh(created_account, **options)
 
+    def update(self, **options):
+        updated_account = self.put("%s/%s" % (self.KILLBILL_API_ACCOUNTS_PREFIX, self.accountId),
+                                   self.to_json(),
+                                   {},
+                                   self.build_options(**options))
+        return self.fromJson(updated_account['body'])
+
     def bundles(self, **options):
-        return self.get("%s/%s/bundles" % (self.KILLBILL_API_ACCOUNTS_PREFIX, self.accountId),
-                        {},
-                        self.build_options(**options))
+        return killbill.Bundle.get("%s/%s/bundles" % (self.KILLBILL_API_ACCOUNTS_PREFIX, self.accountId),
+                                   {},
+                                   killbill.Bundle.build_options(**options))
 
-    def close(self, cancel_all_subscriptions, write_off_unpaid_invoices, item_adjust_unpaid_invoices, user, reason=None, comment=None, **options):
+    def close(self, cancel_all_subscriptions, write_off_unpaid_invoices, item_adjust_unpaid_invoices, user, reason=None,
+              comment=None, **options):
         return self.delete("%s/%s" % (self.KILLBILL_API_ACCOUNTS_PREFIX, self.accountId),
                            "{}",
                            {
@@ -56,9 +64,31 @@ def close(self, cancel_all_subscriptions, write_off_unpaid_invoices, item_adjust
                                **options
                            ))
 
+    def invoices(self, with_items=False, with_migration_invoices=False, unpaid_invoices_only=False, audit='NONE',
+                 **options):
+        return killbill.Invoice.get("%s/%s/invoices" % (self.KILLBILL_API_ACCOUNTS_PREFIX, self.accountId),
+                                    {
+                                        'withItems': with_items,
+                                        'withMigrationInvoices': with_migration_invoices,
+                                        'unpaidInvoicesOnly': unpaid_invoices_only,
+                                        'audit': audit
+                                    },
+                                    killbill.Invoice.build_options(**options))
+
     @classmethod
     def find_by_external_key(cls, external_key, **options):
         query_params = {
             'externalKey': external_key
         }
         return cls.get(cls.KILLBILL_API_ACCOUNTS_PREFIX, query_params, cls.build_options(**options))
+
+    @classmethod
+    def find_by_id(cls, account_id, account_with_balance=False, account_with_balance_and_cba=False, audit='NONE',
+                   **options):
+        relative_url = "%s/%s" % (cls.KILLBILL_API_ACCOUNTS_PREFIX, account_id)
+        query_params = {
+            'accountWithBalance': account_with_balance,
+            'accountWithBalanceAndCBA': account_with_balance_and_cba,
+            'audit': audit
+        }
+        return cls.get(relative_url, query_params, cls.build_options(**options))
diff --git a/killbill/bundle.py b/killbill/bundle.py
new file mode 100644
index 0000000..aa7a770
--- /dev/null
+++ b/killbill/bundle.py
@@ -0,0 +1,31 @@
+#
+# Copyright 2014-2017 The Billing Project, LLC
+#
+# The Billing Project, LLC licenses this file to you under the Apache License, version 2.0
+# (the "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at:
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+import killbill
+
+
+class Bundle(killbill.Resource):
+    KILLBILL_API_BUNDLE_PREFIX = killbill.Resource.KILLBILL_API_PREFIX + '/bundles'
+
+    def __init__(self, **d):
+        super(Bundle, self).__init__(d)
+
+    @classmethod
+    def find_all_by_account_id_and_external_key(cls, account_id, external_key=None, **options):
+        relative_url = "%s/%s/bundles" % (killbill.Account.KILLBILL_API_ACCOUNTS_PREFIX, account_id)
+        query_params = {
+            'externalKey': external_key
+        }
+        return cls.get(relative_url, query_params, cls.build_options(**options))
diff --git a/killbill/catalog.py b/killbill/catalog.py
new file mode 100644
index 0000000..fd93a60
--- /dev/null
+++ b/killbill/catalog.py
@@ -0,0 +1,46 @@
+#
+# Copyright 2014-2017 The Billing Project, LLC
+#
+# The Billing Project, LLC licenses this file to you under the Apache License, version 2.0
+# (the "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at:
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+import killbill
+
+
+class Catalog(killbill.Resource):
+    KILLBILL_API_CATALOG_PREFIX = killbill.Resource.KILLBILL_API_PREFIX + '/catalog'
+
+    def __init__(self, **d):
+        super(Catalog, self).__init__(d)
+
+    @classmethod
+    def available_addons(cls, base_product_name, **options):
+        relative_url = "%s/availableAddons" % cls.KILLBILL_API_CATALOG_PREFIX
+        query_params = {
+            'baseProductName': base_product_name
+        }
+        return killbill.PlanDetail.get(relative_url, query_params, killbill.PlanDetail.build_options(**options))
+
+    @classmethod
+    def available_base_plans(cls, **options):
+        relative_url = "%s/availableBasePlans" % cls.KILLBILL_API_CATALOG_PREFIX
+        query_params = {}
+        return killbill.PlanDetail.get(relative_url, query_params, killbill.PlanDetail.build_options(**options))
+
+    @classmethod
+    def catalog(cls, requested_date=None, **options):
+        relative_url = cls.KILLBILL_API_CATALOG_PREFIX
+        options['accept'] = 'application/json'
+        query_params = {
+            'requestedDate': requested_date
+        }
+        return cls.get(relative_url, query_params, cls.build_options(**options))
diff --git a/killbill/custom_field.py b/killbill/custom_field.py
new file mode 100644
index 0000000..b03aa11
--- /dev/null
+++ b/killbill/custom_field.py
@@ -0,0 +1,22 @@
+#
+# Copyright 2014-2017 The Billing Project, LLC
+#
+# The Billing Project, LLC licenses this file to you under the Apache License, version 2.0
+# (the "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at:
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+import killbill
+
+
+class CustomField(killbill.Resource):
+
+    def __init__(self, **d):
+        super(CustomField, self).__init__(d)
\ No newline at end of file
diff --git a/killbill/invoice.py b/killbill/invoice.py
new file mode 100644
index 0000000..f6520d5
--- /dev/null
+++ b/killbill/invoice.py
@@ -0,0 +1,42 @@
+#
+# Copyright 2014-2017 The Billing Project, LLC
+#
+# The Billing Project, LLC licenses this file to you under the Apache License, version 2.0
+# (the "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at:
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+import killbill
+
+
+class Invoice(killbill.Resource):
+    KILLBILL_API_INVOICE_PREFIX = killbill.Resource.KILLBILL_API_PREFIX + '/invoices'
+
+    def __init__(self, **d):
+        super(Invoice, self).__init__(d)
+
+    @classmethod
+    def find_by_id_or_number(cls, id_or_number, with_items=True, audit="NONE", **options):
+        relative_url = "%s/%s" % (cls.KILLBILL_API_INVOICE_PREFIX, id_or_number)
+        query_params = {
+            'withItems': with_items,
+            'audit': audit
+        }
+        return cls.get(relative_url, query_params, cls.build_options(**options))
+
+    @classmethod
+    def as_html(cls, invoice_id, **options):
+        relative_url = "%s/%s/html" % (cls.KILLBILL_API_INVOICE_PREFIX, invoice_id)
+        options['accept'] = 'text/html'
+        options = cls.build_options(**options)
+        options['method'] = 'GET'
+        options['queryParams'] = {}
+        raw_get_response = cls.send_request(relative_url, options)
+        return raw_get_response['body']
diff --git a/killbill/payment_method.py b/killbill/payment_method.py
new file mode 100644
index 0000000..aaf7e2f
--- /dev/null
+++ b/killbill/payment_method.py
@@ -0,0 +1,86 @@
+#
+# Copyright 2014-2018 The Billing Project, LLC
+#
+# The Billing Project, LLC licenses this file to you under the Apache License, version 2.0
+# (the "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at:
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+import killbill
+
+
+class PaymentMethod(killbill.Resource):
+    KILLBILL_API_PAYMENT_METHODS_PREFIX = killbill.Resource.KILLBILL_API_PREFIX + '/paymentMethods'
+
+    def __init__(self, **d):
+        super(PaymentMethod, self).__init__(d)
+
+    @classmethod
+    def get_refresh_query(cls):
+        return {'withPluginInfo': True}
+
+    def create(self, is_default=True, user=killbill.user, reason=None, comment=None, **options):
+        created_payment_method = self.post("%s/%s/paymentMethods" %
+                                           (killbill.Account.KILLBILL_API_ACCOUNTS_PREFIX, self.accountId),
+                                           self.to_json(),
+                                           {'isDefault': is_default},
+                                           self.build_options(
+                                               user=user,
+                                               reason=reason,
+                                               comment=comment,
+                                               **options
+                                           ))
+        return self.refresh(created_payment_method, **options)
+
+    def set_default(self, user=killbill.user, reason=None, comment=None, **options):
+        self.put("%s/%s/paymentMethods/%s/setDefault" %
+                               (killbill.Account.KILLBILL_API_ACCOUNTS_PREFIX,
+                                self.accountId, self.paymentMethodId),
+                               "{}",
+                               {},
+                               self.build_options(
+                                   user=user,
+                                   reason=reason,
+                                   comment=comment,
+                                   **options
+                               ))
+        return self.find_by_id(self.paymentMethodId, **options)
+
+    def destroy(self, delete_default_pm_with_auto_pay_off=False, force_default_pm_deletion=False, user=killbill.user,
+                reason=None, comment=None, **options):
+        return self.delete("%s/%s" % (self.KILLBILL_API_PAYMENT_METHODS_PREFIX, self.paymentMethodId),
+                           "{}",
+                           {'deleteDefaultPmWithAutoPayOff': delete_default_pm_with_auto_pay_off,
+                            'forceDefaultPmDeletion': force_default_pm_deletion},
+                           self.build_options(
+                               user=user,
+                               reason=reason,
+                               comment=comment,
+                               **options
+                           ))
+
+    @classmethod
+    def find_all_by_account_id(cls, account_id, with_plugin_info=False, **options):
+        relative_url = "%s/%s/paymentMethods" % (killbill.Account.KILLBILL_API_ACCOUNTS_PREFIX, account_id)
+        query_params = {
+            'withPluginInfo': with_plugin_info
+        }
+        return cls.get(relative_url, query_params, cls.build_options(**options))
+
+    @classmethod
+    def find_by_id(cls, payment_method_id, plugin_property=None, included_deleted=False, audit='NONE', with_plugin_info=False, **options):
+        relative_url = "%s/%s" % (cls.KILLBILL_API_PAYMENT_METHODS_PREFIX, payment_method_id)
+        query_params = {
+            'pluginProperty': plugin_property,
+            'includedDeleted': included_deleted,
+            'audit': audit,
+            'withPluginInfo': with_plugin_info
+        }
+        return cls.get(relative_url, query_params, cls.build_options(**options))
diff --git a/killbill/plan_detail.py b/killbill/plan_detail.py
new file mode 100644
index 0000000..e164fb8
--- /dev/null
+++ b/killbill/plan_detail.py
@@ -0,0 +1,28 @@
+#
+# Copyright 2014-2017 The Billing Project, LLC
+#
+# The Billing Project, LLC licenses this file to you under the Apache License, version 2.0
+# (the "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at:
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+import killbill
+
+
+class PlanDetail(killbill.Resource):
+
+    def __init__(self, **d):
+        super(PlanDetail, self).__init__(d)
+
+    @classmethod
+    def dict_to_object(cls, d):
+        if 'plan' in d:
+            return cls(**d)
+        return d
\ No newline at end of file
diff --git a/killbill/resource.py b/killbill/resource.py
index 5146a61..a246c0a 100644
--- a/killbill/resource.py
+++ b/killbill/resource.py
@@ -45,7 +45,7 @@ def __init__(self, d):
             setattr(self, key, value)
 
     def __repr__(self):
-        return '%s %s' % (self.__class__, self.to_json)
+        return '%s %s' % (self.__class__, self.to_json())
 
     @staticmethod
     def build_options(**options):
@@ -63,9 +63,13 @@ def build_options(**options):
     def to_json(self):
         return killbill.json.dumps(self, default=lambda o: o.__dict__)
 
+    @classmethod
+    def get_refresh_query(cls):
+        return {}
+
     def refresh(self, raw_response, **options):
         url = raw_response['response'].headers['Location']
-        return self.get(url, {}, self.build_options(**options))
+        return self.get(url, self.get_refresh_query(), self.build_options(**options))
 
     @classmethod
     def fromJson(cls, jsonString):
@@ -96,6 +100,13 @@ def delete(cls, relative_uri, body, query_params, options):
         options['queryParams'] = query_params
         return cls.send_request(relative_uri, options)
 
+    @classmethod
+    def put(cls, relative_uri, body, query_params, options):
+        options['method'] = 'PUT'
+        options['body'] = body
+        options['queryParams'] = query_params
+        return cls.send_request(relative_uri, options)
+
     @classmethod
     def send_request(cls, relative_uri, options):
         headers = {}
diff --git a/killbill/subscription.py b/killbill/subscription.py
index e89e41a..5e36336 100644
--- a/killbill/subscription.py
+++ b/killbill/subscription.py
@@ -23,7 +23,8 @@ class Subscription(killbill.Resource):
     def __init__(self, **d):
         super(Subscription, self).__init__(d)
 
-    def create(self, user, reason=None, comment=None, requested_date=None, call_completion=False, **options):
+    def create(self, user=killbill.user, reason=None, comment=None, requested_date=None, call_completion=False,
+               **options):
         query_params = {}
 
         if call_completion:
@@ -43,3 +44,108 @@ def create(self, user, reason=None, comment=None, requested_date=None, call_comp
                                              **options
                                          ))
         return self.refresh(created_subscription, **options)
+
+    def change_plan(self, update, user=killbill.user, reason=None, comment=None, requested_date=None,
+                    billing_policy=None, call_completion=False, **options):
+        query_params = {}
+
+        if call_completion:
+            query_params['callCompletion'] = call_completion
+
+        if requested_date:
+            query_params['entitlementDate'] = requested_date
+            query_params['billingDate'] = requested_date
+
+        for key, value in update.items():
+            setattr(self, key, value)
+
+        updated_subscription = self.put("%s/%s" % (self.KILLBILL_API_ENTITLEMENT_PREFIX, self.subscriptionId),
+                                        self.to_json(),
+                                        query_params,
+                                        self.build_options(
+                                            user=user,
+                                            reason=reason,
+                                            comment=comment,
+                                            **options
+                                        ))
+
+        return self.fromJson(updated_subscription['body'])
+
+    def cancel(self, requested_date=None, call_completion=False, call_timeout_sec=5, entitlement_policy=None,
+               billing_policy=None, use_requested_date_for_billing=False, plugin_property=None,
+               user=killbill.user, reason=None, comment=None, **options):
+
+        query_params = {}
+
+        if requested_date:
+            query_params['requestedDate'] = requested_date
+        if call_completion:
+            query_params['callCompletion'] = call_completion
+        if call_timeout_sec:
+            query_params['callTimeoutSec'] = call_timeout_sec
+        if entitlement_policy:
+            query_params['entitlementPolicy'] = entitlement_policy
+        if billing_policy:
+            query_params['billingPolicy'] = billing_policy
+        if use_requested_date_for_billing:
+            query_params['useRequestedDateForBilling'] = use_requested_date_for_billing
+        if plugin_property:
+            query_params['pluginProperty'] = plugin_property
+
+        return self.delete("%s/%s" % (self.KILLBILL_API_ENTITLEMENT_PREFIX, self.subscriptionId),
+                           "{}",
+                           query_params,
+                           self.build_options(
+                               user=user,
+                               reason=reason,
+                               comment=comment,
+                               **options
+                           ))
+
+    def add_custom_fields(self, custom_fields, user=killbill.user, reason=None, comment=None, **options):
+        query_params = {}
+        custom_fields_response = killbill.CustomField.post(
+            "%s/%s/customFields" % (self.KILLBILL_API_ENTITLEMENT_PREFIX, self.subscriptionId),
+            killbill.json.dumps(custom_fields),
+            query_params,
+            self.build_options(
+                user=user,
+                reason=reason,
+                comment=comment,
+                **options
+            ))
+        return killbill.CustomField().refresh(custom_fields_response, **options)
+
+    def remove_custom_fields(self, custom_field_list=None, user=killbill.user, reason=None, comment=None, **options):
+        query_params = {}
+        if custom_field_list and len(custom_field_list) > 0:
+            query_params['customFieldList'] = ','.join(custom_field_list)
+
+        killbill.CustomField.delete("%s/%s/customFields" % (self.KILLBILL_API_ENTITLEMENT_PREFIX, self.subscriptionId),
+                                    "{}",
+                                    query_params,
+                                    self.build_options(
+                                        user=user,
+                                        reason=reason,
+                                        comment=comment,
+                                        **options
+                                    ))
+
+    def custom_fields(self, user=killbill.user, reason=None, comment=None, **options):
+        query_params = {}
+        return killbill.CustomField.get("%s/%s/customFields" % (self.KILLBILL_API_ENTITLEMENT_PREFIX, self.subscriptionId),
+                                        query_params,
+                                        self.build_options(
+                                            user=user,
+                                            reason=reason,
+                                            comment=comment,
+                                            **options
+                                        ))
+
+    @classmethod
+    def find_by_id(cls, subscription_id, audit='NONE', **options):
+        relative_url = "%s/%s" % (cls.KILLBILL_API_ENTITLEMENT_PREFIX, subscription_id)
+        query_params = {
+            'audit': audit
+        }
+        return cls.get(relative_url, query_params, cls.build_options(**options))