FWIW... "horse apples" from a bois d'arc tree repel fleas really well.When I had fleas try to invade my house a few years back, I bought the cheapest bagless unit that WalMart had to use in the places they were; it did a decent enough job.
We had 'em infest the carpet once (weird, because we had no house pets), and I put one or two horse apples on paper plates under furniture throughout the house. They were gone within a week or so.
We kept finding dried-up horse apples for months...