This was sent to me from my Husbands Grandmother by Email. I’m not sure who had this idea but it’s a good one.
How to Keep Flies away:
Fill a Ziplock Bag with water then add 5-6 pennies and seal it up.
Hang it where the Flies are a problem. Some say this works with Wasps too. (I hung mine up by punching a hole above the seal and using a shoe lace through the hole).
The bugs mistake the bag for other insect nests and are threatened. Or it could be that they see their reflection and think it’s another bug. Either way I’m told that it works!