flea foggers

I have inherited a house and had some cats inside when we weren’t staying there yet they ended up getting fleas. The cats are not inside anymore but the fleas are so bad that we can not move in. We have vacuumed and set out flea foggers and still when you walk in your pants are immediately black with fleas. I don’t know how to get rid of them. The floors are hardwoods and tile.

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