My downstairs neighbor is a heavy smoker, and my bedroom and bathroom frequently reek of cigarette smoke. Being a nonsmoker myself, I find the smell highly offensive. Fortunately airing out the room, combined with the fact that I have a Sharper Image Ionic Breeze Quadra, keeps the smell down to a tolerable level.
You may be able to create positive air pressure in your apartment that should prevent such odors from comming in. actually all you need is positive air pressure along the side where the odor is. If you have vents you may be able to ajust them so more air is being put into that side then taken away. If it is possible it will cost a little more to heat the place most likly but it may not be much.
Polycarp - groan I can’t believe you got away with that one!
StG