We actually do automate as much as possible (small team, lots to do). We've a Fabric script that sets up a complete new environment for a customer/tenant in one go. That includes creating and populating the virtualenv, creating a new database + database user etc. If the command is finished the customer basically is able to log in. And that script is actually only about a 200 lines of code or so.

The nice thing of Fabric is that it makes automating something hardly more work than doing something in a one-off fashion.