Smoking on Premises

[Catie Fihn]

We inherited tenants in a duplex we bought several months ago.  They have been very good tenants and we have no complaints.  Our only concern is that they smoke in their downstairs unit of the property.  We just finished rehabbing the upper unit and are now looking for renters for the upper.  With the lower tenants smoking downstairs, and the smell of their smoke wafting into the upstairs, we are concerned that smoke smell will turn some potential renters away.

I know we need to honor the lease that the tenants were under before we bought the property.  Their lease does not have a no-smoking policy.  Are we able to tell them that they can't smoke in the house?