Ceiling Paint if possible, may have to replace panels it its a drop ceiling as the smoke permeates all the pores4.

Also the best thing I've found for cleaning tar/nicotine stains, btw (my least favorite thing in the entire world, I would rather clean out a chicken coop)

I'm looking to permeate through every facet of this business with vigor and passion.

We did a super nicotine special about 15 months ago.

Cost me $7,500 to replace the heat pump, the tenant stole, and get the nicotine out of the walls.  

Bad news for investors.Recently had an REO listing where the home needs an entirely new roof and the 3rd floor needs to be gutted from leaks that permeated down into the 1st floor kitchen.Never thought an owner occupant would want to buy this house.

wont the other tenants complain about the smoke permeating the building 

Tenant's sign a "No smoking" in the apartments addendum.No Butts, No Smell, No Nicotine stained walls.

Tell tenant frankly that pet smells and you are concerned about getting complaints from other tenants (as if you haven't yet) and clean up costs for pet odor permeating walls/surfaces/floors etc. -- which you want to avoid to avoid having to deduct security deposit charges (or increase security deposits next time around in order to pay for pet cleaning/deodorizing).

Mix TSP and water to scrub the walls, it'll pull the nicotine out.