The best solution is find how they get in. The techniques to mouse / bat control are the same as in weatherization, Seal up all holes. I had a similar situation with mice in a former home. A mouse can move through a very small hole (I was told 3/8" is all they need). I seached several times for any opening. I finaly found a dip in an extra wide mortar joint where the sill meets the block (the tool I used to find this was my wife's scream as she saw a mouse crawl in it). I caulked that hole! That night there were mice everywhere looking for a way out(just because you don't see them, doesn't mean there not there). After that, no mice.
Look for any holes in the soffit, siding, where pipes & wires go through. Check the weatherstripping on the doors & windows. Check the foundation & sill. CAULK EVERYTHING!