Haha yes fly-paper will do the trick ofcourse but its a little more cruel then my methods however there is a point where those flies can reach your level of patience and your just like '' fuck those damn flies" and you go full berserk on them with products,traps, fly-paper,.. But I hope you will find a way to solve your problem with methods like this oh and btw I also use mosquito windows everywhere in the house that is like a MAJOR advantage. ^^