We developed a rat problem in our house. I trapped several including one the size of a wharf rat. We put out rat poison. Still had rats. A neighborhood cat that is one of several that neighbor ladies feed started coming to my door and I fed it a couple of times then invited it into the house. Now we have a regular deal. I feed it good food each evening and it comes into the house and wanders around meowing everywhere in the house then wants back out after 20 minutes or so. We have not any more evidence of rodents. The cat is worth its pay.