The results of hiring an unqualified contractor can be devastating. Here is an example: A roofing
contractor claimed to be a mold remediation contractor. He removed the roof decking and replaced it with new painting over framing (and mold) in the attic space. What you see in the photo is the result of 1 years time. The contractor did not bother to assess of correct the ventilation issues (cause) And painting over mold is wrong no matter what the circumstances.
Do your research. Hire a professional