Had mice several times before. They wear hobnail boots! You could hear them scuttling about. Eliminated them by having a tree close to the house culled, among other unsavoury measures. My DD’s partner is a forester and he keeps the tree in check, cutting down branches correctly and at the right time of the year. The bats don’t make a noise, and we don’t go up in the attic that often. Too cold. Putting the light on may disturb them. Tough. DH actually disturbed them in the other attic, which is connected to the main attic. They flew round him.. We’ve always had bats flying around our house. And we have no plans on building works involving the attic. Looked into that years back. Because of how the roof was constructed it would have to be removed! Too expensive. We keep stuff in plastic boxes up there.