Don't smoke in your car. Back when I smoked somewhat regularly (even then it was only a pack a week, these days I only smoke when drinking which isn't very often), I would never smoke in my car, ever. If I wanted one while driving, I would pull into a parking lot, step outside and have one. Slight inconvenience, but having a car that doesn't smell like smoke is 100% worth it. You WILL burn a hole in your interior at some point, plus, who wants to be vaccumming out ash every week? And, if you get smoke in your eyes (happens to me quite frequently) it could potentially be a huge safety hazard.