Tenants cat left allergens

[Bill Hoo]

What is the best way to get rid of cat dander after tenants have departed?

Tenant violated the NO PETS policy in the lease and got a cat.  Claimed it was his mother's and only had on weekends.  

I had reminded them of the no pets policy a few months ago when I was escorting the hvac tech thru the property and I saw cat toys and a litter scoop on the kitchen counter.

Lease was ending anyway and they decided not to renew.

Did the walk thru with them last night and was suprised at how clean the place was.  I noted that departing tenants had never wiped the window sills, or cleaned the carpets before.  They said they had hired a professional cleaning service and I thanked them for that.  As I was walking thru, I started sneezing and my sinuses were irritated.

They left behind an unopend 42 LBS bag of cat litter.

30 minutes after they had left, my nose was watery, eyes had swollen up, throat got a bad tickle, and I felt itchy and fevered.  CAT DANDER!

Also notice the smell of piss all over the kitchen area.  I still have their deposit.  ($2750).