The dogs all have fleas, or you are just trying to prevent them?
Of course, I am going to assume they do, so here are a few 'pointers'...
Get some DE from the garden center of any walmart\\target and sprinkle that all over your carpets, yard, their bedding etc...you can vacuume it up later. That's supposed to help kill and control fleas without the 'pesticide' factor.
Most regular pet shampoos will smother and kill fleas if left on the coat long enough, so just get a good shampoo...perhaps a citrus type one, and bathe the dog thoroughly, and let him soak for 10-15 minutes in the shampoo. This will not kill any eggs, so you will need to bathe the dog quite often to keep the population from spiking again; and you'll have to bathe every pet in the home, and sprinkle the DE all over again, as well.
You could get some frontline spray, for some of the more hidden areas, that the dogs can't access, or for treating toys, and extra bedding (which you'll seal into a garbage bag for a week or two, after spraying with the frontline). You can then wash all of this extra stuff before presenting to the dogs again.