[You would be surprised to know that smoke can travel in air vents and ducts from condo to condo. Even if you do not smoke if your neighbor does, it can get into your unit.]
Twas the case in my previous condo. I lived happily for two years until Mr. Smoker moved in next door. I had masking tape over the phone jacks, etc. but it just kept finding its way in.
I lived in pre-war apartment buildings in NYC for more than 50 years and never had that problem. Maybe they’re not builing them as well these days.