ISO cat flea treatment (preferably Advantage...)

After bringing home a new kitten (who brought home fleas...), my cats have been suffering. My two older cats are allergic, biting themselves until they scab. I used the one application of the natural flea meds I had, and it didn't help at all. I can not afford any more flea meds right now since we just bought our first house. I bathe them and borax the carpets, but it's not enough. DorrisWedding bat mitzvah gowns

Any help would be greatly appreciated.