My day job is as a certified mold investigator. 75% of my clients are sick in some way as a result of mold exposure.
I see far too often where people purchase homes that have moisture issues and they do not take them seriously. Then down the road they (or their tenants) start to get sick, or the leak/staining gets worse, etc., and the issue finally must be dealt with. This can be a big expense, as well as a legal issue if you're dealing with tenants.
I've seen the majority of investors I've come in contact with downplay water and/or mold issues, and it's really irresponsible. I give the benefit of the doubt assuming they just don't know any better. But as landlords we have a responsibility to provide healthy homes for tenants (and ourselves).
I personally budget mold remediation into my rehab expenses when looking at properties. Most people don't do this because it will hurt their numbers for the deal. But sometimes money isn't the most important thing. This is probably why I pass on many properties. What ends up happening is mold issues get overlooked or covered up, and the end buyer ends up inheriting those problems.
I could talk about this all day, but what I'd say is:
If there is a water leak, there is likely a mold issue as well. You should take that into account when making your decision.
