The only sure way to remove any mold, does not matter on species, is to remove the moisture.

NOT AN APPRAISER - But usually they look at permanent fixtures (eg swimming pool) as an adjust to the comps used.However, if there is obvious major CapEx needed (eg roof with major holes and obvious moisture invasion issues) sometimes they'll take that into account, but they are NOT physical inspectors and don't know the cost.  

Then, once you treat/fix the problem, you just need to take some basic steps to prevent them from coming back (i.e. eliminate any areas of wood-to-ground contact, address any moisture issues, etc). 

@Donovan JamesHere is what I typically ask/look for in a house-Age of roof-Age of furnace-Age of water heater-is the electrical updated-Check for any major cracks in the foundation-If you are flipping the house see the age and condition of all windows-Check for moisture and mold in the basement-Check for any large cracks in walls-Check all ceilings for water marksYou may also be able to find a check list of things to check in a walkthrough on google.

Moisture / water / mold, knob & tube wiring, foundation issues, ancient plumbing, rust on the breaker panels, termite tunnels, powder post beetle damage, cedar post supports, improper footings, temporary lally columns, etc.As to writing an offer, that's a sensible and common approach. 

I would not touch a property like this, but if you really LOVE it, check with a crawlspace encapsulation company(if they exist there) and get a price to stop moisture rising from the ground and rotting your wood subfloor

You know there was a good couple years there that my wife wasn’t seeing the vision but I just kept presenting stuff to her gently and helping her to see what’s possible and eventually she decided “yup, let’s get free, I’m in.”

They seem to believe that all of this moisture damage is related to a lack of proper guttering on the sides of the house.

.• Moisture is present in the soil under the raised foundation.Due to the amount, we recommend all the post and pierinspected for signs of settling.Page 14 Item: 7 FoundationPlumbing• Plumbing- Main drain line.

A lot of back and forth with the appraiser and hiring a Realestate attorney to gently force her hand......