So I will back away from renovations and major improvements.

To me it actually looks like they partially/fully remediated the mold.My question is: As an investor, what is my obligation to notify potential buyers that there is mold present in a home that I will be completely renovating?

 I'm about to start renovating my rental to get ready for appraisal and refinance.

I bought a triplex last year and an currently renovating the units.

One of the very large boilers is pretty old (other pretty new) but the building itself appears in good shape (had a fire 2009 but renovated). 

I find a renovators risk policy to be the best for this situation.  

They were all bought at the height of the market from 2006 thru 2008 and all are in need of full renovation.

I'm a fairly serious DIY kind of guy having built 3 houses, renovated a manufactured home, built several small barns and about to renovate a vacation home we just bought "up north" as we Michiganders like to say.  

(renovation will start from the out side, then unit by unit as they move).

The VAs that come to me are after the property has been renovated and it is being bought by a retail buyer on the back end.