If you find your house has been infested by insects it is important to be aware of the different methods to get rid of these creatures and what the associated costs are. There are three types of extermination techniques which come with different costs. With chemical extermination, expect a starting cost of $1200. Bait extermination will cost you $2000 on average, and finally heat extermination can cost $1800 on average. Most fumigators will charge by the square foot when they treat your home.