Re: Fleas! (kinda ranty)
Just wanted to add that I didn't have any luck with Frontline. I have found Advantage to work great every time though. Others swear by Fronline so, I don't know if it's certain pets chemistry or the fleas in some areas are immune to the drug in one or the other but, it's worth trying.
Although I hate using them, I agree that with an infestation that bad, a fogger may be your best answer. It's a major drag but works. In the days before spot treatments I had to do it several times. Take the kitties to the groomers for a bath (I'd do a regular bath not a flea bath in your case and then apply Advantage...as long as it's been long enough since the Frontline). Meanwhile bomb the house. Wait 4 or whatever hours...go for lunch, have a manicure, whatever. Then vacuum everything and throw away the vacuum bag, out of the house! Clean everything well and air the place out well...actually, do that before you go in there to clean! Bring your flea free kitty home! One last thing, and this is a common oversight, treat your car! I can't tell you how many times I've come across people who keep getting re-infested and it's because they were in their car. So, when you come home from dropping off your cat, and before you clean the house, spray your car well with flea spray and air that out while you're cleaning house. Phew! I'm exhausted!!
Now I have one other thought. If you have an untreated basement or crawl space, spray that as well. If you have the nasty critters living under the house, they'll keep poppong up.