When we moved into a house years ago that had a horrible flea infestation, the landlord had the Orkin man come out three times to fully take care of the problem. The carpet and drapes (which were already there before we moved in) were both involved. The previous tenant had apparently been an eccentric old fellow with a zillion dogs in the house. The three trips were to take care of the emerging generations of fleas that appeared after the initial spraying.
It is my understanding that most 'home remedies' are not usually strong enough to take care of a really serious infestation.
Good luck!
I will add that the Borax mentioned above works well for 'water bugs', also called palmeto bugs or giant roaches. Have not tried it for fleas.