I've posted about this before, but, the best thing that you can do for your house and your dog/yourself is to treat your house with diatomaceous earth. Food-grade is the safest, but there's nothing wrong with using non-food-grade as long as you vacuum up all of the loose powder.
If you treat your entire house (carpets, floors, couches, etc.) with diatomaceous earth, it will kill all fleas and flea larvae that would otherwise hatch/live in your carpets, floors, and couches - and it will keep killing them for up to a year, as long as you don't use a steam-cleaner type of thing on your carpets. It basically ensures that your house can't get infested, since neither fleas nor flea larvae can live wherever there is diatomaceous earth. And so then, if you treat your dog once a month with one of the monthly flea treatments (Frontline, Advantage, etc.), then even if they bring the occasional flea into the house, neither your dog nor your house will get infested despite the occasional flea that comes in from the outside. Fleas that bite your dog will die because of the treatment on your dog, and any eggs they lay in the house will die because of the diatomaceous earth.
I had a huge flea problem when I first moved into my place, because the previous tenants had had cats with fleas. And before I moved in, the property manager flea-bombed the place. Two to three weeks after I moved in, I was getting bitten, and the property manager then called a professional exterminator. Three weeks after they came, I was getting bitten again... and the property manager called them again and they came back. Three weeks after that, I was getting bitten again, and it was then that I decided to take things into my own hands... I found out about the diatomaceous earth and applied it, and I haven't had a flea problem since, even when Ceylon brought fleas home when I was late in giving him his monthly flea treatment. Diatomaceous earth really, really works! Give it a try