I'm going answer this against my better judgment. I do not mean to offend. If you keep animals of any type in your yard or house and have uncovered trash cans anywhere on the property as well as standing water, which also produces mosquitoes, than you have to change a few things. If you have animals and can't get rid of them you must feed them the best dog/cat food you can afford. Nutro-Max produces the driest smallest, driest waste of them all and also provides the best nutrition, and pick up animal waste every day in plastic bags and tie it up and put it in the trash. Keep trashcans covered. Check anything that could hold standing water even an 1/8th cup of water. Make it drain or get rid of it. If you have a fly problem you have a breeding ground somewhere. Find it and fix it. Forget the chemicals. If it is you neighbors yard insist that they do something. Their flies are causing you big problems. It is not hard to get rid of flies permanently but you do have to take action. I rarely see flies around my house. My dog is picked up after each day, all trashcans are covered tight, All trash is tied shut in plastic bags. I let no standing water accumulate,and I keep my BBQ pit clean and closed and I do not have a fly problem. Hope this helps.