A friend of mine is experiencing some pretty significant mold in his house since the big rains here in L.A., and asked me for help/advice. I don't know much about it, other than it is bad and can make you sick, so I am putting it to the brain trust here.
The house was significantly remodeled maybe 10(?) years ago, if that is relevent, and the mold is appearing on drywall in the garage/guest house area, visible on the interior walls in places.
He called a "mold expert" from the yellow pages who basically offered to test his house for mold for $600, (like he doesn't already know that he has mold),

, so how does one get rid of it? Any help or advice is appreciated, TIA.