Give specific details on the location e.g. is it in the attic, under roof tiles, inside the building, in a tree hole, underneath bark of a tree:
We live in a old house by the forest and we have been living here for 5 years now. We've had bats in the attic from the beginning, they are really fast and come out in the evening to fly/hunt around the house. There are always 3 of them and we believe they were 4 when we moved here. They are really fast, but we have been watching them a lot and believe they are dvärgpippistrell (Pipistrellus pygmaeus). We see them come out of a hole under our roof, so they seem to live in the attic. We like them very much and enjoy that they are here.