It removes odors from smoking, pets, food, teenage boys, etc.I purchased an apartment complex and one of the units had smokers in it for over 30 years.

New carpet/flooring, repaint everything including the kitchen and bathroom cabinets, remove any wallpaper and replace drapes worked on my house that had heavy cigarette odor and yellowing.

Here's a quote from Google on search topic "ozone removes odors":An ozone generator will not only remove pet odors but other troublesome odors caused by mold and mildew, fire, water damage and others.

I still smell the odor, and I hope to start on the walls today.Ofgift

But maybe I am just going nuts with all this....Anyway, the Carpet guy advised to spray Lysol ON and ABOVE carpet and vacuum with pet odor killing powder.Before I do that, I wanted to see if there are other suggestions.Thanks :help:

In addition to removing lower portions of walls, I recommend Kilz stain/odor blocking on all surfaces, even the ceiling. 

I can smell a very strange odor coming from their upstairs rooms (again, their apartment is attached to my house) and it’s so strong that it’s coming through my guest bedroom and even into my landing.

@Peter Morgan When it comes to renting with pets, there always be some negatives such as - damage to your apartment, disturbance to your neighbors, pet odors, etc.

For example, my lease has the following clause in it:NEIGHBORHOOD CONDITIONS: Tenant is advised to satisfy him or herself as to neighborhood or area conditions, including schools, proximity and adequacy of law enforcement, crime statistics, proximity of registered felons or offenders, fire protection, other governmental services, availability, adequacy and cost of any speed-wired, wireless internet connections or other telecommunications or other technology services and installations, proximity to commercial, industrial or agricultural activities, existing and proposed transportation, construction and development that may affect noise, view, or traffic, airport noise, noise or odor from any source, wild and domestic animals, other nuisances, hazards, or circumstances, cemeteries, facilities and condition of common areas, conditions and influences of significance to certain cultures and/or religions, and personal needs, requirements and preferences of Tenant.

Search BP for information on "cat odor".