If you see one mouse you should assume he's having an entire family reunion behind your wall boards. The trick is to eradicate the nest without leaving fresh corpses. The click and squeak of a mouse trap going off in the night is disconcerting as well. There are steps to take that will eliminate the problem without noxious fumes and there are other steps to ensure the marauding mice don't return.
Set an appropriate sized trap for your rodent.The perfect trap snaps the mouse's spine but if it's too hefty it will cut the carcass in half and make an ugly clean-up. Traps often have size indications stamped on them. Bait traps with anything because rodents don't care whether it is cheese or popcorn.
Set a catch and release trap. The rodent goes in after the bait and the trap door falls. He is not injured and you can remove him to the woods if you wish. The only caution is that mice never come in singles and you will make several trips to the woods before the family is completely out of the house.
Consider nature's food chain in eliminating mice. Choose a feline for mousing duties because cats are always interested in catching mice. Be aware that cats tend to torture them, but even the scent of a cat or its litter box is a great deterrent to the mouse population and they may flee on their own.
Rid your home of mice chemically. Use a commercial poison called D-Con, which is a hydroxycoumarin that attracts mice who eat it and cart it back to their nests where the chemical dehydrates them. Try this because there is rarely an odor from their bodies because they are desiccated.
Clean the house thoroughly and store food properly. Do not leave unwashed dishes or food out to attract a whole new generation. Stuff rodent holes with steel wool to cut off access. Employ these methods to help eradicate rodents and keep them away.