diff --git a/TODO.md b/TODO.md
index 5e39f70b..bc86b844 100644
--- a/TODO.md
+++ b/TODO.md
@@ -119,7 +119,6 @@ Remember that, as always with QuerySets, any subsequent chained methods which im
 * delete main user -> delete account or prevent delete main user
 
 * Ansible orchestration *method* (methods.py)
-* pip upgrade or install
 * multiple domains creation; line separated domains
 * Move MU webapps to SaaS?
 
@@ -156,5 +155,6 @@ textwrap.dedent( \\)
 * parmiko write to a channel instead of transfering files?  http://sysadmin.circularvale.com/programming/paramiko-channel-hangs/
 
 * strip leading and trailing whitre spaces of most input fields
-* Examples of service.match and service.metric
 
+* better modeling of the interdependency between webapps and websites (settings)
+* webapp options cfig agnostic
diff --git a/orchestra/apps/domains/backends.py b/orchestra/apps/domains/backends.py
index 282953a1..cc263a3d 100644
--- a/orchestra/apps/domains/backends.py
+++ b/orchestra/apps/domains/backends.py
@@ -133,7 +133,7 @@ class Bind9SlaveDomainBackend(Bind9MasterDomainBackend):
             'name': domain.name,
             'banner': self.get_banner(),
             'subdomains': domain.subdomains.all(),
-            'masters': '; '.join(self.get_masters(domain)) or 'none',
+            'masters': '; '.join(self.get_masters(domain)) or '"none"',
         }
         context.update({
             'conf_path': settings.DOMAINS_SLAVES_PATH,
diff --git a/orchestra/apps/domains/forms.py b/orchestra/apps/domains/forms.py
index fead09de..0c46670d 100644
--- a/orchestra/apps/domains/forms.py
+++ b/orchestra/apps/domains/forms.py
@@ -24,6 +24,46 @@ class DomainAdminForm(forms.ModelForm):
         return cleaned_data
 
 
+#class BatchDomainCreationAdminForm(DomainAdminForm):
+#    # TODO
+#    name = forms.CharField(widget=forms.Textarea, label=_("Names"),
+#            help_text=_("Domain per line. All domains will share the same attributes."))
+#    
+#    def clean_name(self):
+#        self.names = []
+#        target = None
+#        for name in self.cleaned_data['name'].splitlines():
+#            name = name.strip()
+#            if target is None:
+#                target = name
+#            else:
+#                domain = Domain(name=name)
+#                try:
+#                    domain.full_clean(exclude=['top'])
+#                except ValidationError as e:
+#                    raise ValidationError(e.error_dict['name'])
+#                self.names.append(name)
+#        return target
+#    
+#    def save_model(self, request, obj, form, change):
+#        # TODO thsi is modeladmin
+#        """ batch domain creation support """
+#        super(DomainAdmin, self).save_model(request, obj, form, change)
+#        if not change:
+#            for name in form.names:
+#                domain = Domain.objects.create(name=name, account_id=obj.account_id)
+#    
+#    def save_related(self, request, form, formsets, change):
+#        # TODO thsi is modeladmin
+#        """ batch domain creation support """
+#        super(DomainAdmin, self).save_related(request, form, formsets, change)
+#        if not change:
+#            for name in form.names:
+#                for formset in formsets:
+#                    formset.instance = form.instance
+#                    self.save_formset(request, form, formset, change=change)
+
+
 class RecordInlineFormSet(forms.models.BaseInlineFormSet):
     def clean(self):
         """ Checks if everything is consistent """
diff --git a/orchestra/apps/domains/models.py b/orchestra/apps/domains/models.py
index 01171103..1b40eb99 100644
--- a/orchestra/apps/domains/models.py
+++ b/orchestra/apps/domains/models.py
@@ -11,9 +11,10 @@ from . import settings, validators, utils
 
 class Domain(models.Model):
     name = models.CharField(_("name"), max_length=256, unique=True,
-            validators=[validate_hostname, validators.validate_allowed_domain])
+            validators=[validate_hostname, validators.validate_allowed_domain],
+            help_text=_("Domain or subdomain name."))
     account = models.ForeignKey('accounts.Account', verbose_name=_("Account"),
-            related_name='domains', blank=True, help_text=_("Automatically selected for subdomains"))
+            related_name='domains', blank=True, help_text=_("Automatically selected for subdomains."))
     top = models.ForeignKey('domains.Domain', null=True, related_name='subdomains')
     serial = models.IntegerField(_("serial"), default=utils.generate_zone_serial,
             help_text=_("Serial number"))
diff --git a/orchestra/apps/miscellaneous/models.py b/orchestra/apps/miscellaneous/models.py
index 6de14273..7b4f82fd 100644
--- a/orchestra/apps/miscellaneous/models.py
+++ b/orchestra/apps/miscellaneous/models.py
@@ -1,4 +1,5 @@
 from django.db import models
+from django.utils.functional import cached_property
 from django.utils.translation import ugettext_lazy as _
 
 from orchestra.core import services
@@ -34,6 +35,13 @@ class Miscellaneous(models.Model):
     
     def __unicode__(self):
         return "{0}-{1}".format(str(self.service), str(self.account))
+    
+    @cached_property
+    def active(self):
+        try:
+            return self.is_active and self.account.is_active
+        except type(self).account.field.rel.to.DoesNotExist:
+            return self.is_active
 
 
 services.register(Miscellaneous)
diff --git a/orchestra/apps/services/handlers.py b/orchestra/apps/services/handlers.py
index c666dc9c..2d39ca5c 100644
--- a/orchestra/apps/services/handlers.py
+++ b/orchestra/apps/services/handlers.py
@@ -45,6 +45,9 @@ class ServiceHandler(plugins.Plugin):
         return ContentType.objects.get_by_natural_key(app_label, model.lower())
     
     def matches(self, instance):
+        if not self.match:
+            # Blank expressions always evaluate True
+            return True
         safe_locals = {
             'instance': instance,
             'obj': instance,
diff --git a/orchestra/apps/services/models.py b/orchestra/apps/services/models.py
index aa8e3351..6647e439 100644
--- a/orchestra/apps/services/models.py
+++ b/orchestra/apps/services/models.py
@@ -100,8 +100,19 @@ class Service(models.Model):
     }
     
     description = models.CharField(_("description"), max_length=256, unique=True)
-    content_type = models.ForeignKey(ContentType, verbose_name=_("content type"))
-    match = models.CharField(_("match"), max_length=256, blank=True)
+    content_type = models.ForeignKey(ContentType, verbose_name=_("content type"),
+            help_text=_("Content type of the related service objects."))
+    match = models.CharField(_("match"), max_length=256, blank=True,
+            help_text=_(
+                "Python <a href='https://docs.python.org/2/library/functions.html#eval'>expression</a> "
+                "that designates wheter a <tt>content_type</tt> object is related to this service "
+                "or not, always evaluates <tt>True</tt> when left blank. "
+                "Related instance can be instantiated with <tt>instance</tt> keyword or "
+                "<tt>content_type.model_name</tt>.</br>"
+                "<tt>&nbsp;databaseuser.type == 'MYSQL'</tt><br>"
+                "<tt>&nbsp;miscellaneous.active and miscellaneous.service.name.lower() == 'domain .es'</tt><br>"
+                "<tt>&nbsp;contractedplan.plan.name == 'association_fee''</tt><br>"
+                "<tt>&nbsp;instance.active</tt>"))
     handler_type = models.CharField(_("handler"), max_length=256, blank=True,
             help_text=_("Handler used for processing this Service. A handler "
                         "enables customized behaviour far beyond what options "
@@ -132,8 +143,16 @@ class Service(models.Model):
                         " membership fee or not"))
     # Pricing
     metric = models.CharField(_("metric"), max_length=256, blank=True,
-            help_text=_("Metric used to compute the pricing rate. "
-                        "Number of orders is used when left blank."))
+            help_text=_(
+                "Python <a href='https://docs.python.org/2/library/functions.html#eval'>expression</a> "
+                "used for obtinging the <i>metric value</i> for the pricing rate computation. "
+                "Number of orders is used when left blank. Related instance can be instantiated "
+                "with <tt>instance</tt> keyword or <tt>content_type.model_name</tt>.<br>"
+                "<tt>&nbsp;max((mailbox.resources.disk.allocated or 0) -1, 0)</tt><br>"
+                "<tt>&nbsp;miscellaneous.amount</tt><br>"
+                "<tt>&nbsp;max((account.resources.traffic.used or 0) -"
+                " getattr(account.miscellaneous.filter(is_active=True,"
+                " service__name='traffic prepay').last(), 'amount', 0), 0)</tt>"))
     nominal_price = models.DecimalField(_("nominal price"), max_digits=12,
             decimal_places=2)
     tax = models.PositiveIntegerField(_("tax"), choices=settings.SERVICES_SERVICE_TAXES,