This picture is from a ranch style house basement, where the house has been sittting vacant, with no heat or utilities on for over 8 months. The damage seen is not from an external leak from a roof or foundation; it is from condensation cuased by the neglect of beingclosed up with no heat, or ventilation.
This is a typical bank-owned property, that really has no management of the property, other than to make sure it is locked up. I see this type of damage more and more, with all the foreclosures and bank REO'S.
The thing is, I don't think most bank real estate departments have any idea what kind of damage they are causing, or how difficult it is to repair, and all because of simple neglect.
This home has extensive mold in the entire basement, as well as some 1st floor ceilings, and all the window sills. The damage will cost more than $18,000 to repair, and could go much higher, if there is evidence of mold inside the wall cavities, and insulation.
Mold damage, when it gets to this point, is really well beyond the scope that any amateur, or homeowner should try to do on their own. The risks of becoming sick, or hyper-sensitive to mold are greatly increased, and if not handled properly, you can actually cause more damage, by spreading the spores to other areas. Respirators, gloves, protective clothing, and sometimes elaborate containment methods are needed to deal with it, as well as proper disposal tecniques.
Bank owned, or repos may actually be endangering neighbors and neighborhoods with this kind of neglect, since spores become airborne, and can travel several hundred yards.