I think you are mixing things up.
Fleas, once inside, will not go anywhere. They don't migrate back outside, you can't ask them to leave.
There are only two things they are designed to do in life. Multiply and feed.
They multiply fast. And once they start they life cycle can hibernate from anywhere between 12 days to 174 days. Each female can produce 100 offspring a week.
They prefer to feed on animals, but if animals aren't available, or don't taste too nice, they will gladly feed on human species.
Considering all of the above, unless you suspect fleas outside and you don't have them yet inside, there is NO scenario, upon which you would want to REPEL them. Repelling, means moving them deeper into carpets and hibernation and re-occurring issues for months. Repellant on your animals means they will feed on you.
Do not repel. Kill. Eradicate. That is what you want to do. Murder the motherlovers. You have three well established, working choices.
- Smoke bombs (proper industrial grade stuff, if off the shelf, go for Raid or Beaphar stuff, none of the Dr. Martins cack).
- Indorex.
- Flea drops, where your pet is used as a weapon, fleas go to feed on them, byte them then die horrible death. Among those the best is Beyer Advantage/Advocate, then long, long nothing, then Frontline. Don't use any of the supermarket stuff, you don't want to be saving money - it needs to kill, it needs to last, it needs to come in a pack of three so you can keep killing them for at least quarter of a year.