i must agree with Jman8 that it is possible to completely eradicate smoke smell, even in a house where we smoked previously, I did it.
when i quit, i did a major, weeks-long deep cleaning project in here, and i managed to get it clean-smelling and smoke free.
I used "TSP", a professional painters' cleaning product used specifically for smoke-mitigation and soot removal after house fires. I micro-cleaned, and i mean MICRO - in addition to the obvious (carpets, bedding, mattresses, linens, curtains, clothing, windows, walls, floors, ceilings (and ceiling fans) and furniture), i went down to the level of - yes, with Q-tips - inside the heating vents, in the cracks of the baseboards, woodwork, and floorboards, every tiny channel around the windows, inside the air conditioner and refrigerator heating and colling units, the framework of the drop-ceiling around the ceiling tiles - i mean everywhere. it's VERY intensive and takes a lot of time - but it can be done.