Sorry to hear about that @Rhonda140 - it’s not pleasant trying to get the smell out. Chlorine based cleaner will get it out of any surfaces (including plastic bin inners), so use that to wipe down first, then go over it with something more pleasant smelling. If the bedding smells, use wool mix to soak and hand wash them out (eucalyptus smell is best!) - learned this from my wife, she’s got all kinds of tricks for stain and smell removal...
We have a penalty listed in our rules that applies in this situation, but it’s intended as a deterrent. I doubt we would bother enforcing it if it happened, it’s more a case of setting a firm tone in the hope it will prevent smoking issues.
This is a shortened version:
SMOKING POLICY
No smoking is permitted anywhere inside the property. We reserve the right to charge a $250 instant penalty, plus extra cleaning fees and cost of future lost business, if the cottage smells of smoke or contains smoking related litter.
We display our 1 page of rules as a poster, standing picture, and in a house manual, as well as on Airbnb... 4 different ways just to be sure they are seen. We also translate it into different languages if we have foreign guests.
Also, I recommend getting those various little no smoking signs to put around the place. We have small discrete ones, but they are effective because we have dotted them around above light switches (people are going to see them when the use the light switch). Make sure it’s not just a sign in English words, but also a sign that includes the universal symbol for no smoking (cigarette in a red circle, with a line through it) then you are covered.
Hopefully this will help you get ahead of any repeat issues.