It will probably take me that long to mitigate the cigarette smell regardless.

Apt G claims that she smelled cigarettes and it was so bad it was seeping into her apt and she has health problems.

The first is that he smokes cigarettes and pot (not legal here) in his apartment for which we have had complaints about (as the smell travels) from both the apartment above him and from the renter of the commercial space below him.

Pretty sure these are your prospective guests:Rod GrubbRosie GrubbAt least they don't have social media pictures like some of my prospective tenants that end up showing themselves smoking pot and cigarettes (they swear they don't smoke), all their dogs (they swear they don't have pets) and their posts are full of relationship drama (my girlfriend won't be here)So you've got that going for you....

We see the Car there everyday and night and the new person brought me last months rent.On top of that we are now smelling Cigarette smoke through the walls since they ”moved in.”What should I do?

If the units are reasonably clean and in good condition and there aren't piles of stuff/junk everywhere and the place doesn't smell like mold, weed or cigarettes its a good sign.  

In the upper unit, the tenant has lived there for a number of years and smokes inside the unit - it's definitely going to need some work to address the cigarette smoke/tar build up. 

In Calif with a licensed MFU 5+, the fire marshal requires working CO+Smoke detectors and annually replaced extinguishers.In 2013 a cigarette lit the couch on fire and we suffered $95k damages. 

I thought about implementing a fine system where if I smell smoke or see a cigarette butt, then they get a $50 fine.

We're finishing up a flip right now that had super bad cigarette smoke and cat pee.