Bats feed off of mosquitoes and other insects, and therefore have become a very effective form of mosquito repellent. The most effective way to attract bats to your property is with a bat house. Bat houses are usually tall, single-chamber houses which are capable of housing up to 50 bats at one time. Larger, multi-chamber bat houses are available and are known to attract colonies of 200 or more bats. Bat houses are simple to build and assemble. They are most effective at attracting occupants when mounted on buildings or trees that are located away from power lines to secure the safety of the bats. Bat houses can cost anywhere between $20 and $100 online, depending on the size and quality of the bat house.