I've made a cursory sweep of each level, but more of my focus has been on the second floor.

[ Under the assumption that second floor windows were more likely to be less secure, logic that may have helped if they were in anything approaching a normal house. ]

I say we focus on the attic, first. [ Though it looks like Kurogane is already doing that. ] If that doesn't yield results, we can reinspect the rest of the house.