Smoke residue is chemically active. Within days it etches chrome, pits aluminium window frames and appliance trim, and yellows any surface with a finish on it. Fabric and carpet take a permanent set. The damage that gets argued about with insurers months later mostly happened in the first week.
So the order matters: secure and board up, get the power and gas situation resolved, pull the air through filtration, and start on the surfaces that corrode first — not the ones that look worst.
And the fire service will have put a great deal of water into the building. Almost every fire job we run is a water job as well, which is why the drying equipment arrives at the same time.