Help Please - Advice on Cockroach Infestation in AZ

[Andrea Finkelstein]

Hi everyone! 'Hope everyone is staying healthy and doing well. I own condos and one of my tenants has had a growing brown banded cockroach problem for about the last 4 months. My tenants are extremely clean and vigilant. The infestation seems to be coming from an adjacent property or one in the building (8 condos - 4 on main floor, 4 2nd floor units). In our unit, we have sealed up all 'holes' we can find. Treated with professional grade products such as bait gel, growth inhibitor, bait stations, diatomacious earth, boric acid, raid, bleach in the drains, and more. Called the city and asked them to treat the sewers (although these aren't sewer roached). Last night my Tenants woke to two crawling on their bed. So disgusting! The HOA says all they can do it send a letter requesting the owner of the problem unit to treat and then have them provide proof (which they said they had done because they said they knew who was causing the problem - but, I learned today it was another building!). We don't know where the problem is stemming from, and they won't notify the problem 'owner' if we can't give them a unit number. They have treated around the perimiter, to no avail. Professional exterminators won't treat one attached condo for an infestation - tried 3. Most of these units are renter occupied, and some are even Sec 8. Has anyone delt with an infestation in a condo type of property where you don't own all the attached units? Or, would anyone happen to know what other options are available to me? Thanks in advance!