Mice are a pain. I've attracted a mouse or two while we've called the Silver Bullet home. Seems they go straight to my stash of chocolate so they've never lived long enough to put in a change of address. The wife's has glue traps everywhere. The cat has found several which she (KittyKat nor the wife) does not appreciate. I've put poison in a lot of out of the way places. In the 345 there are a lot of out of the way places: under the drawer, under the bed, under the couch, by the heaters, behind the frig and the list goes on.
Good luck with the mouse eviction process and cleanup.