I use a Gamo Whisper pellet gun in .177 caliber. Very quiet when you use standard lead pellets. I managed to slay 400+ ground squirrels with it while not alerting my neighbors. Also since its quiet, I could knock off the rodents friend with a follow up shot as he was watching his now deceased friend and trying to figure out what just happened. In my experience, repellants are a waste of money. You need to get rid of any food, water or shelter source that brings them in. Traps and poisons can be had but the poisons will affect other critters, like your pets, as the target rodent doesn't always croak in its nest/hole. Regardless of what the bait manufactures say about the bait blocks being pet friendly, the pet can die too or at a minimum get seriously jacked up. Any varmint that I could hit that fell into the effective range on the .177 got hit. Keep them slain for a good distance around your house and you won't have very many issues.