You may not be the only victims of the fleas. Based on your post, I suspect there are critters in or under the structure that are part of the picture. Also, the bombs only function to kill the fleas for a few minutes. Once the odor is gone, usually an hour or so, the pesticide is no longer effective. The problem with your approach is that at least two stages of flea life are unaffected by your treatment. Eggs and pupae are not at all effected. Additionally, the bombs do not penetrate all flea sites, so some adults and larvae will survive. The unaffected stages will mature and renew your problem every day. Since the life cycle of the flea is quite long, the products you choose need to last through their cycles. Using something like CG recommends is important. This will help your pets, but will not effect other animals like mice rats squirrels skunks and anything else that could be living in or under the structure. I suggest you get a residual pesticide like orth-os home defense to treat the carpet and cat hiding spots. Google and read up on your problem. You'll find tons of detail if you search.