My neighbor downstairs smokes all the time in his apartment. He has a live/work space with a storefront. My lease doesn't allow smoking, and I'd assume his doesn't either. Both my girlfriend and I have talked to him about it many times, but it's just getting worse. It literally smells like someone is smoking in our apartment. All our clothes, furniture... everything smells like smoke. We've talked to the landlord about it, but he's a really passive guy and I don't think he would enforce this, especially since the neighbor is his longest tenant and was there before the upstairs was even finished. Also the neighbor is a really nice guy, active in the neighborhood, and I don't want to make him an enemy, but it's really bad and we can't live with it anymore. What would you do?