I tried everything and finally started using flea and tick killer on my dogs. I have the neighbors cats passing through my property as well as deer, skunks, ground squirrels, and field mice. I could wipe out every flea in my house and on the dogs and as soon as they go back outside they are going to pick up fleas and adult ticks.
I could wipe out every flea and tick on the property by having a crop duster do a dump of poison and within days the ticks and fleas will be back in force.
In my area heart worms are passed along by fleas and about 32 types of bacteria that infect and damage humans are known to be carried by the ticks in the state so I am not about to take a chance with some home remedy.