We only ever had 3-4 bats in the house each summer, but it made each evening filled with dread about the possibility that one might show up. I was not happy about the price and considered alternatives but Ben made some good points. He came and after 7 hours had filled every opening in our brick century home, leaving 3 escape routes for the bats. Since then we have had all the weather conditions that encourage the bats to make an appearance - cool weather, hot nights, thunderstorms - and not a single flutter! I feel the money spent was a worthwhile investment and would encourage anyone to check this company out first!