Yes, you could try to convince the tenant that you're right and it's not a problem after cleaning it with bleach - but if they disagree and are looking for a way to not pay rent it could make managing the situation a nightmare.

While I don't disagree with this approach (to each their own), I feel it promotes tenant retention, rents the units faster and you can get a small premium that will pay for itself in a year or so at most. 

I disagree with your reasoning a bit, and here's why.You're waiting to flip 2 properties before you'd consider buying or mortgaging a rental unit.

I am sure there are some that would disagree.  

@Stephen E.There are may types of rooming houses ... if you search on here, there are a couple of threads where I've put them in 3-4 categories (I tend to waiver whether there are really four):  student, institutional (i.e. employer such as a factory or hospital), and social (those on the edge of society.I disagree with your categorization - it is overly broad.We have a student rooming house and almost bought another last month (save the deal came apart at the 11th hour).  

We all learn some things on these forums and even from feedback that we disagree with or dislike.  

@Lane Kawaoka I would disagree that 99% of the deals are junk.  

I don't disagree, but lots of people use google.

He figured deals he found on his own doesn't concern his broker, but his broker apparently disagreed.

- Ola  I would need to disagree with this statement.