E.g. Paperwork not to forget, items to document, things to expect when dealing with insurance, etc. I'm looking to avoid stupid mistakes from things I just didn't think of.
I'll forward the discussion along to the thousands of others in a Facebook group facing the same situation.
Grab your homeowner's policy and any small personal items, like wedding rings.
It is cool if you can grab personal hygiene items, but those are relatively easily replaced. Try to take prescription medications. People sometimes wind up seriously ill a week or more after an evacuation event because they don't have their usual drugs and can't readily get more. In some cases, people die a few months later and relatives speculate that it is partly because they couldn't get a steady supply of their usual meds in the weeks afterwards.
Edit: After the fire, when you go back, take photos and call an insurance adjuster immediately. Do this before you try to fix anything or do any clean up. Cleaning up amounts to destroying evidence.
You can hire a public adjuster to file for you. Your broker, lawyer or a public adjuster are essentially the only people that can talk to the insurance company on your behalf.
(Edit: changed private adjuster to the correct term public adjuster)