Discussions

I think the best way would be to take off the cushions and air it out for a few days. (providing it doesn't rain!) Maybe put it in your garage or porch or something like that. After that I would Febreeze it.

I think if you steam cleaned/shampoo it the smell would leave. The entire couch though, front, back, under the cusions, sides.

You most likely will never get all the smell out, unfortunately.  
 
It will depend on how long the people owned it, how heavy they smoked, and what it is made of.  
 
I stored my velvet like plush foam sofas at my parents home for three months while out new house was being readied and it sucked up enough tar and crap that I never was able to get the smell out. We covered every square inch with baking soda and left it for days, vacuuming it up - nothing. We tried bottles of febreeze and vinegar, enough to soak it through into the foam cushions, and still you can't get right into the wood frame to get all the smell. We even left them outdoors in the winter for over a month to no avail.  
 
She tried to give me an arm chair that was fabric as well and we locked it in a small trailer with an ozone machine for three straight days after cleaning the fabric and that too, failed.  
 
The only thing we have found that mitigates smoke residue is borax - that is how I had to clean any clothes my mother brought for the kids. Unfortunately, you may never get the borax in to the deep recesses of furniture for it to help - and it may leave a bad residue. This like polyester I have thrown out after dozens of washings because once in it never comes out.  
 
If you can leave it out doors for a while and spray it heavily with vinegar it may be your only shot.

But coffee works wonders. Sprinkle on and vaccume up later. Also a bit of vodka in a spray bottle to spray the whole couch. Let air dry

Try this product. You can buy it at Prairiewest for around $10  
http://prairiewestproducts.com/product/aa-010-attack-orange-odor-counteractant-and-air-freshener/

Do not use fabreeze, it only covers smell, usually it will smell worse after, a mix of fabreeze & smoke!! You can by odor ellimators at sports stores for hockey bags works great. If you can take the cushion covers off, wash them and hang dry. There is also a spray to get odor out of shoes (shoe store) that worksa wonders to

And shampooed the rest with a carpet cleaner yesterday morning. I was very happy to see that the water wasn't very dirty. My co-worker did say they hardly used it! Once couch was dry I sprayed it last night with a 1:2 ratio of vinegar and water. This morning I'm happy to say no smell!! Yet! Hopefully it stays that way!! I think if the smell had been severe it would still "stink"!! Yikes. So glad I don't smoke!!