I'm the person who soaks my skin in Deet because mosquitoes eat me alive. Yes, I've tried Skin so Soft and citronella, lemongrass and eucalyptus oils. Mosquitoes backstroke in that mess as they collectively steal a pint.
I'm a hypocrite, sort of. I won't use chemicals on my yard. I believe if worms would rather wriggle out of the soil and writhe in a horrible death on a scorching, summer sidewalk, then it can't be good for the planet.
I don't use poison on vermin, nor will I use a live-catch trap. (You don't want to know about the time I didn't check on one for weeks.) I prefer a snap trap for a quick death.
All of that is to say; I will gladly use chemicals to keep fleas off my four dogs and off of me.
I've had a flea-infested house before. It took months of chemicals to get rid of those buggers. I even tossed out my pepper for a time, just because it caused flashbacks to that nightmare.
What product do you like the best? Oh, it must also repel, kill or scare the bejesus out of ticks.