If you know of a small child that now has brain damage due to PAST exposure to the meth, then there may be a moral obligation to let the parents know what happened.But if the units don't share common ventilation or there is otherwise a minimal or very low risk that other areas of the building were contaminated, then I think you can sleep easy at night knowing that there was likely to be no damage or issue elsewhere and the landlord took care of the issue.Stirring up drama over something that is no longer an issue is not in anybody's best interest.  

What if you start to feel like the deposit won't cover the damages they are doing to the property?

I'd price utilities into the rent, I'd also provide basic furnishings to mitigate move in/out damage. 

I'll get a metal roof and I estimated it at about $6,000.One front door is near where two roof angles meet, and I imagine the gutter couldn't take on the stream at that intersection, because there's water damage on the inside of that wall that leads to the basement/garage.

The realtor mentioned it may not be able to be financed with a traditional lender so I'm concerned about how much damage it may have but I'll be taking a look at it tomorrow to try and get an idea. 

The exterior brick damage would be easily apparent, as well as a brief visit to a unit and common areas.

You'll want to keep money in reserves in the event that one of your rentals cannot wash it's own face (evictions, excessive repairs or damages, etc.)

She believes it is due to some water damage that happened over a year ago in the basement.

A quality BR policy provides replacement cost coverage for materials owned by you and your subcontractors, have no exclusion for theft, vandalism leaking pipes or water damage.

I'm not sure how badly it was damaged, but based on the pictures I was sent I know I won't be able to rent any of the apartments out for quite awhile.