You must hire a company that approved in your state.
But, in some states, such as VA, you don't have to release the information that your house had mold before. You just need to totally remove them. Not hard to do that.
Spray bleach, then Kilz, then put on anti-mold drywall, then paint ...
It is used to be a big issue so you can be sued for that, but now, the judge most likely would say, every house has mold.
