Pull out your insurance policy, and contact the insurance company. Notify your insurance agent of the loss; later, if you need help, the agent can quickly respond to your needs.
Review the policy and consider the benefits of seeking advice from a competent insurance loss professional. These reviews will identify steps you need to take to preserve and present a claim to your insurer, and offer guidance with uninsured losses (such as tax consequences).
Flood insurance, through the National Flood Insurance Program (NFIP), may be managed by your insurance company, or by the NFIP through its contractors. In all cases, whether the NFIP policy is sold through an insurer or with the NFIP directly, the NFIP's rules and requirements will be followed. The NFIP policies are available online.
Follow my survival tips to reduce your stress.
Organization is key! Use painters masking tape and a large marker to identify each damaged item with a unique, sequential number. Use that number to identify everything connected with that item: receipts, advertisements, items on spreadsheet lists, and photographs. If you have enough people, divide tasks: movers, numberers, list makers & photographers.
I suggest these additional, specific steps for organizing your contents claim.
If you have insurance, and have called your insurer, you will receive a call from an adjuster assigned by the insurance company. This individual may either be a company adjuster, or an independent adjuster hired for that claim. The adjuster will take steps to identify what is covered under the policy, and estimate the loss for your damages.
Whether or not your loss is insured, take immediate steps to mitigate damages! Insurance policies will require that you do so; and potentially penalize your claim if you do not.
Prepare to show your adjuster all the details of the loss. Your preparation will go a long way towards assisting your adjuster to fully and accurately document the claim to your insurance company. While a professional adjuster may notice more damage than you initially identify, your preparation and documentation remains the most important tool in restoring your business, home or other property to its original condition.