Investors have a more difficult dilemma. Typically a landlord should disclose to a potential tenant anything that could materially affect their decision regarding renting the home prior to renting it. Things such as mold related issues should be disclosed. If not, your liability greatly increases if the tenant finds out at a later date and you did not disclose it.
Mold issues can affect the economics of an investment property. Will a home with a prior mold problem rent at market rents? Will the resale value be less than market value?
This is not to say that a mold issue can not be properly mitigated and a clearance certificate issued for occupancy. However, if a tenant or child develops asthma, allergies or other upper respiratory related problems for no apparent reason the landlord's property could easily be blamed for it. The causation of these problems to the home would be very difficult to determine but it does put the landlord in the position of having to defend themselves with no insurance backup. We have all seen insurance companies exclude mold from their policies leaving everyone financially responsible themselves.
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