Small (heh) flea problem

Magus`

So I recently moved to a new place and things are mostly find. However lately I've noticed some small amounts of fleas (and sometimes feeling like there are fleas but can't see anything?). Given that I am meticulous about cleanliness after living in a place that smelled like cat pee 24/7, I can assure you I've been very proactive to avoid this.

Info to know:
I have one pet, a rat. I did not see any fleas on it.
The only actual visible fleas have been seen on the couch which was a floor model.
I get the feeling of bug bites a lot on my bed.
I have noticed a fair amount of dead flies and Asian lady beetles (not ladybugs) here and there. There was a shitton of them in the back/laundry room.

Besides putting a towel under the back room's door and in the process of getting some diatomaceous earth to put at various windows (I'm told it's effective), what should I do? I plan to call the rental company about the back door letting bugs in, but since I'm on the second floor I'm not 100% how sure this is the source of fleas.

Also I'm told certain smells repel them. Is this true?

Edit: I have sprayed my mattress and couch with Hotshot Flea/Bed Bug spray. I also considered lice* but given I have black sheets and such you'd think they'd be visible.

* As a caseworker I don't always work with the cleanest people. I try to remain very hygienic myself.

Inquisitor77

I doubt it's fleas, or you would know for sure. They're very conspicuous and bite constantly. If you're only getting bites at night, you could very well have a bed bug problem, which can't be solved just by spraying your bed and cleaning your linens. Basically you have to carpet bomb your entire building (yes, building), in addition to a bunch of other stuff like potentially getting rid of your mattress and cleaning the shit out of everything you own in hot water. A similar problem would be rat mites, which are caused by nearly-invisible bugs which feed off of rats but transfer to humans and bite the shit out of us because why not. The thing with them is that you have to get rid of the rats first, or the mites will just keep coming back. Thankfully, unlike bed bugs, they don't require high-ordnance chemical warfare to kill off entirely - once you get rid of the rats the mites go away because they can't live off of anything else. If you have a pet rat it's possible that the poor little guy caught it from somewhere else and is now a vector, so you may need take him to the vet to get cleaned up and taken care of.

Really, your best bet is to get an exterminator and let them diagnose the problem. They will likely need to set out a few different traps to confirm your problem, and then can address it once they know for sure what the deal is.

Magus`

I'll talk to my rental people and see about an exterminator, then! Thanks for the thorough answer!