If you can find these things

1. Commercial demuhidifiers (if you're contractor doesn't have these things or if they do but they can't make it out immediately)
2. Industrial blowers

Absolute needs

1. Gloves
2. Particulate masks
3. Good heavy shoes
4. Wheel barrow/moving equipment
5. More trash bags than you think you need
6. Fans (any random fans if you can't find blowers)
7. Water (for drinking)
8. A clean, large table to keep tools, phones, water on while you work
9. Broom
10. Shovel

If you can't find a contractor immediately (all for ripping out drywall)

1. Claw head hammers
2. Toolbelts
3. Crowbars
4. A reciprocating saw

Optional (if you're not going to dry everything out in a timely manner)

1. Bleach
2. Hand pump chemical sprayer
3. Mold spray

These three things won't stop mold, but it'll slow the mold growth if you're not able to remove wet stuff in time.