here's the story of how our little bungalow is going from 1980s drab to 1913 fab
Are they bees or are they hornets? If they're honey bees, get someone to come out and remove them (beekeepers!), if hornets, then kill away (windex works great). Honey bees are endangered and we need all the colonies we can get. I don't know about your state, but it's illegal to kill a honey bee colony in illinois unless you have absolutely no other option.
As someone who has been through it (my house came with two active hives in it, and we've had countless swarms since), you may be able to have a beekeeper come and move them for you (assuming they're honeybees). Honeybees are in trouble at the moment, and exterminators aren't actually supposed to kill them, look up local apiaries, and good luck!