Please don't move this nest - as Avatar says, it's illegal to disturb nesting birds. Once the basic nest is built and a hen is enticed to come and join him in his lovely new home, she will line the nest with moss, feathers and other soft stuff then lay her eggs and incubate them, usually 4-6 eggs. It's highly unlikely either parent will be wandering around your attic - they will be far too busy looking after the eggs and then feeding the babies when they hatch about 12 days after laying. They will stay in the nest until they are ready to fledge(at about 3 weeks of age) and will be far more interested in food than in your attic. They will be fed by the parents for another 7-10 days before finally becoming totally independent. What you could do is simply cover your stuff with some dust sheets for the time being. When you no longer hear little chirrups from the attic and see all the starlings gathering together in great flocks, you know you can check on the nest to make sure it's empty. Simply remove the nest and THEN seal the hole where they are getting in.