thanks for the tip about the trap placement. I didn't know that, and had placed them near the wall, but at a ~10cm distance and parallel to it. I figured they would smell the bate....
Coming Wednesday we have our yearly owners meeting, and I'll have it discussed. I was wondering the same. My place hasn't been the cleanest lately, but it must come from 3 floors down or one floor up (or two up if the roof is also a floor for them mice

)