I bought a bass recently and the seller forgot to mention one thing when I asked if there was any issues whatsoever. I'll never forget to ask going forward: "Has the bass been in a smoke free environment?"
I received the bass, opened the case, and almost passed out from the smell. Seriously hardcore stench. I contacted the seller and he said that's how he got it and it didn't bother him. I spent a ton of time, TLC, and money getting rid of the smell, which was unbelievably hard to remove. But I did after a few months. The case is worthless - can't get rid of the smell in it. The seller gave me back some money, but it was a major pain to deal with.
So lesson learned, smoke free means a lot to those who don't smoke. Not being a snob, just prefer not to purposely subject myself to it.