If you notice an infestation of silverfish in your home, you’ll probably want to hire a professional Silver Fish Exterminator. This service usually costs about $200 to $400 per visit and will eliminate the problem once and for all. There are two types of extermination methods: the first involves spraying an insecticide, which kills silverfish by obstructing their digestive systems. The second method involves a mix of boric acid and flour, which is applied to an index card or wallet-sized piece of cardboard. The mixture should dry to a sticky consistency before applying it to the area. Once applied, the paste should be checked frequently to ensure that the silverfish have not moved on.