First you MUST find their entry holes and plug them good. Metal plate is one possible solution, metal shavings down hole etc.
Once ypou plug the entry minimize food sources laying around. all extra dry cat food in sealed metal container. cat food dish to new location far from original local//
then get a live mouse trap, put along walls, not open area. mice have learned open areas lead to death.
Then some peanut butter in trap empty at least twice a day. mice freak when trapped all but the oldest will survive trapping.
Now before you complain I released mine about 50 feet from the house.
Most arent coming and going knowing the way in, their mom snuck in somehow, and they were born, most probably live out their entire life in your home....
warm dry food source, they dont go to the beach:(
The live trap WORKS, One time I evicted over 38 mice:( were mouse free today near as I can tell....
when we remodeled the kitchen I cemented around all openings to the basement since the mice appeared to use too large holes around water lines as expressway.
give the live trap a chance, at least reduce the number you poision.
LIVE TRAP WORKS!