the mold remediation specialist is right. concrete does take years to cure, which can result in moisture on the surfaces of concrete. as such, any carpet on the concrete slab would eventually cause mold. however, you stated that the floor is tile, so, that would not be an issue. 65% is kind of high for humidity, and given the fact that they have too much stuff in the place, that gives the mold spores something to feed on. consequently, they are causing their own problem. since no one else had such a problem prior to them moving in, common sense says that they are the problem. i would offer them a buy out on their lease and send them packing

You want to renew, so it surprises me that this sort of behavior just surfaced.  

I would plan on exploring this from either Sheetrock wall on opposite side of opening up the wall from the tiled surface in the bathroom.You probably will not be able to keep the deposit in this case, and as you mentioned it was a 2 "flat" I am assuming you're in the greater Chicago metro and your L & T laws are very strict there.I would do as another post suggested and either have it repaired by current owner prior to closing to your satisfaction - meaning you are physically on the job site to witness extent of damage or lack there of due to water, or, renegotiate and ask for a concession for the issue - and this could be a moderately expensive problem depending on the length of time it has been leaking and given the possible location of the shower/bath to supporting wall etc should lumber need to be replaced.

A 30" Vanity would increase the width by 6" and add ~25% more surface space, I think that is a valuable improvement especially since there would be more cabinet space as well. 

:) The plastic blinds will likely be stained, particularly in the room(s) where they smoked most frequently.While folks will suggest to prime with a sealant primer (such as Zinnsser), if there have been long-term smokers, it may not be sufficient - it will cover in the short-term, but the toxins will eventually find their way to the surface again.We helped to renovate a house where the prior owner had been a heavy smoker for 30+ years.  

Not that these markets have a ton of value to offer but I am keeping an eye for things that cash flow on the surface. 

The on the surface negatives going in was where all the unrealized value was captured.

baking soda + hydrogen peroxide 3% + laundry soapy solution seems to work best to neutralize the skunks secretions from hard surfaces (and pets fur), spot test first though.for human skin, tomato sauce or ketchup helps neutralize more gently. 

No, Chris said they look the same on the surface, so they are exactly the same no matter what.

Hi @Josh Zephir, on the surface the property you are looking at seems reasonable but there are a few things that give me pause and I would dig deeper into.  1.