To remove mold, first you have to find ALL mold growth, including mold hidden inside walls, ceilings, floors, attics, basements, crawl spaces, and heating/cooling equipment and ducts, as well as mold hidden inside, beneath, and behind kitchen sink cabinets, bathroom vanity cabinets, carpeting and padding, dishwashers, washing machines, furniture, draperies, and wallpaper.
A professional would kill the mold by injecting high output ozone for at least eight hours into each room, attic, basement, crawl space, garage, and into the return air duct of the heating, ventilating, and air conditioning (HVAC) while the HVAC is running on fan ventilation to carry the ozone everywhere in the house or building. This is not something a homeowner is normally equipped to do.
If household items, furniture, house contents can be removed to a pod or other enclosed area, that will expedite the process.
After the ozone, a HEPA vacuum should be used to remove as much mold/mold spores as possible.
The storage room should also be ozoned, then the individual furniture pieces HEPA-vacuumed on all surfaces, and then cleaned. A boric acid will do.
Of course, the homeowner can do all this; but we always recommend that an experienced mold remediation person clean up mold unless it’s just minimal household stuff on bathroom tile walls.