Maintenance of Drupal website + database

We are running 3 websites out of 1 database, the CMS is Drupal 6.15. We are looking for a maintenance-partner on a long term base. Your job is to keep the system up and running: install regular drupal- and security-updates, make minor css- and database-changes. We estimate a maximum of 5 hrs. per month for that. Please make your bid as "per month"; we pay regularily upon invoice. We will not make any advance payment until the work is properly finished. The work is properly finished after tests on your server and a final test on our server. Please do not apply unless you agree with that. Thank you, Reinhard