Display mensual services costs

costs/templates/costs/document_detail.html

@@ -31,7 +31,7 @@
 {% for service in document.service_set.all %}
   <li>
     <a href="{{ service.get_absolute_url }}">{{ service.name }}</a>
-    ({{ service.subscriptions_count }} abonné·e{{ service.subscriptions_count|pluralize:"·s" }})
+    ({{ service.get_prices.unit_recurring_price|price }} /mois)
   </li>
 {% empty %}
   <li>Pas de service pour l'instant.</li>