How to get rid of those pesky little flies?

They’re taking over! Not really, there are only a few, and I kill them when I can but is there anything I can do to deter them from coming in in the first place?

(I’m looking for more a product… not a “call the exterminator” or “close your windows/fix your screens” type of solution. I remember hearing about things that plug into outlets and send some sort of signal out, do those still exist/work?)