Condemn the piano and refuse the job. Black mold is very dangerous to be around or to even touch it because the spores will get into the air. Disturbing it can cause you and the customer respiratory issues Consult with a mold remediation company who should probably bag it up and remove to a hazardous waste disposal site. Lots of articles can be viewed on CDC and other sites. Good chance mold is under the keys in the action etc.
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James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
(843) 325-4357
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