Hi, all *waves*

I haven't posted in a long time, but I have a major issue, and after searching all over the net and consulting with my veterinarian, I am still not sure what to do.
Also, I hope this is the right place to put this, because my problem has to do with .... fleas (which is a cat health issue, yes?)
Let me begin by saying I moved into a new house around August 1st. I brought my two cats with me. I also should add that I live in Southwest Louisiana ... hot and humid ... flea country.
My cats are indoor-only cats and were flea-free when we moved here. However, after one week, I noticed them scratching frantically, so I bought some Advantage. Applied it to each cat, and the scratching stopped ... for about three days.
Then it returned.
I thought this was very odd, until I actually noticed fleas HOPPING ON ME. I realized I had a flea infestation on my hands. Being totally inexperienced on how to deal with this situation, I simply removed myself and the cats from the house and fogged it.
When I returned, there seemed to be no fleas. However ... they returned, again, in 3-4 days.
By this time, my cat Bastet, who is highly allergic to flea bites, had been scratching so much her skin was turning black and she was losing the hair around her neck. It was time for a vet trip.
The vet basically confirmed that they had fleas (it had only been 2-3 weeks since the Advantage application!) and gave me a list of products that I could use to exterminate the fleas from my home. Specifically, he told me about IGRs, an "Insect Growth Regulator" that would prevent the fleas from laying eggs, eggs from hatching, or something to that nature. However, he seemed reluctance to assure me that this would be a sure thing, because of the climate we have here in Southwest Louisiana. He did not think I could get rid of all the fleas, forever.
The cats were given tapeworm pills, just in case. I went home and fogged my house for the time being. Fleas were gone for a few days, but of course returned.
The following weekend, my grandmother gave me some Frontline Plus, which I applied to each cat (one tube each). I then vacuumed thoroughly, with a high-powered shop vacuum, every pieces of material in the house: couch, rugs, sofa chair, cat condo, computer chair, you name it. Then I sprayed the inside and outside of the house (including floors, closets, etc.) with the flea insecticide and IGR mixed with it. I sprayed very thoroughly, to the point of having to cough b/c the fumes were getting in my lungs.
I then waited an hour to let the stuff dry, then let my cats out of the bedroom. I then did the bedroom.
No scratching for a day or two.
Then, on the third day, I found a flea on Bastet.
The next day, both she and Nefrit were scratching.
Yesterday, before bed, I found yet another flea on Bastet.
Please, please, PLEASE ... can anyone help me determine my next move. I am disgusted by the thought of these nasty things crawling all over my darlings. I have done everything a cat mother with limited means (I'm a graduate student, living on 13K a year) can do. I'm afraid to put more Advantage on them b/c the Frontline Plus application was only last Sunday. I know the floor still has the repellent on it b/c it turns my bare feet black after a few hours.
WHAT CAN I DO????