Tip #1: Contact your insurance company and engage professional/licensed electricians, contractors, and consultants before initiating work. Recovery is a marathon, not a sprint.
Tip #2: Be Safe - your safety is by far the most important consideration.
Electricity - if needed, disconnect from power company. Have a licensed electrician look at your system before energizing. Check main disconnect and electrical panel (water there is a bad thing!). Also check appliances for water damage before restoring power. Beware of down wires near your home or business.
Gas - check for leaks or bad connections (sometimes structures and piping move during storms or floods).
Check the structure - don't go in unless you're certain it's safe.
Animals - watch out for animals where you least expect. You never know when you'll run into a scared dog or a snake.
Stay hydrated and wear respiratory protection (check with your physician to be sure you’re capable of wearing a respirator). Also consider wearing a hard hat and eye protection.
Tip #3: Get the building and all the materials in it dry.
Place dehumidifiers & fans in the building. Your air conditioner is better than nothing (but only marginally so).
If no power in the building, open the windows and doors.
Remove wet gypsum board, insulation, and carpet (see Tip #4 below first)!
Tip #4: Beware of other environmental issues.
When you're gutting the building, demolition could disturb materials that contain asbestos, lead, mercury, and PCB. Also watch out for stored chemicals like gasoline, motor oil, and pesticides.
Tip #5: Clean, Disinfect, & Dry.
Get the cleaned up areas white glove clean—no debris or dust or mold should remain. Bleach kills mold & disinfects, but there are other options. Soap (Borax) and water are effective and there is a positive residual effect). Distilled White Vinegar is effective, and you can get it almost anywhere.
Commercial products like Foster's, Microban or Shockwave are pretty good but may be hard to get unless you know a contractor.
No matter what you use, read the Safety Data Sheets and instructions—protect yourself.
Get the building dry and keep it dry.
Tip #6: Salvageable items.
Use a baby pool, bath tub, or bucket as wash stations. Wash dishes and utensils. Launder clothes (you’ll be able to save some of your clothes). Get them dry and keep them dry.
Appliances can sometimes be salvaged—if you dry them and clean them before energizing them. Don’t get electrocuted or cause a fire! Make sure circuits and wiring weren't damaged by water, especially if you think salt water intrusion occurred. Yes, your refrigerator and freezer will be nasty on the inside—but oftentimes can be cleaned and deodorized.
Tip #7: Mold.
Sampling is a waste of time and money before remediation. There is no good mold to grow indoors! Remove moldy materials (check the back of your wall board and sheathing!). Clean the space white glove clean. Conduct a valid Post Remediation Verification visual inspection (and sample now if you think it's needed).
Dry the space and keep it dry. If someone tells you a “Mold Free” certificate is required, run them off! It’s a scam!