Inheriting a tenant who smokes

[Kolton Gutierrez]

So I'm buying a house hack and there is a tenant in the other unit who smokes cigarettes. Would I just need to have them sign a change in term lease addendum and state that this is now a non smoking unit and that all smoking must be done in a designated smoking area? Also, if they already have been smoking inside would I also include in the addendum that any damage caused by the smoking would be deducted from their deposit? I ask the second question because their original lease never stated anything about that so am I wanted to make sure I wasn't going to put myself in hot water by charging them for something that wasn't originally a rule for them.