
Get down to your local Boots the Chemist tomorrow and buy some Acclaim.
It's around £13.50 but the can will treat most normal sized houses, and then some. It also kills house dust mites, which is useful if you have anyone with allergies.
Treatment lasts 6 months - 1 yr and it prevents fleas from breeding in your home. They don't breed on your dog, or cat - they jump off and have fun in your carpets and upholstery before going back to your animals (and in a serious infestation, biting people as well, have been there worn the T-shirt when I was a kid, which is why I am so on the ball about treating the home).
If you have done that then all else is a walk in the park - over the years having lived in rental properties Acclaim has been my best friend: I sprayed before I went in, and before I left, and at intervals in-between.
I have even given half-used cans to friends and neighbours who thought that treating the cats/dogs was enough, only to find themselves bitten.