Keep a digital inventory of your collection, for example in Excel, and make sure it’s up-to-date. List the exact items, their condition, where and when your bought them etc. Be sure to consider and add monetary as well as sentimental value - use color coding or an ABC rating system for the latter, for example with the color red or the assignment of the letter ‘A’ for very important stuff, orange/’B’ for the next etc.
A list like this is will give you a good overview to begin with and helps you decide whether or not to insure specific items as well as what items will need to receive special attention during your disaster-proofing process. Ideally, add pictures and make scans of certificates of authenticity and other important documents. Whatever you do, do NOT store your data on site but save it in the cloud instead!
For smaller items and important documents, invest in a safe that is sturdy enough to survive a hurricane, a flood or a fire. Besides being, well, fireproof, special fireproof safes are usually strong enough to protect items, even if your entire house were to collapse, and water-tight enough to protect against flooding. For extra protection from water, store the safe on a higher floor and seal your items in plastic (ziplocs will generally do).
For items that you like to have on display, that don’t fit in a safe or are ‘not important enough’ to be stored in a safe (yet deserve some precautionary measures), there are several methods to protect them, depending on the type of items and what type of disasters your area is prone to. Protect Items on Display
To protect your treasures on display from seismic hazard and other forces of impact, first of all avoid glass shelves and display cabinets. Use sturdy shelving instead and solidly secure your shelves to the wall – best is to attach a screw to a stud, avoid just anchoring into drywall. In addition, avoid placing fragile items on the top shelf, where they’re more prone to fall down and get damaged. You can also opt to secure items in place, using either hook and loop fasteners on the shelve and object, or non-damaging adhesives such as earthquake putty, gel or wax (yup, these really exists!) to secure breakables in place. These types of substances, commonly used by museums to hold exhibit pieces in place, can be purchased at hobby stores, collectible shops and online. Protect Items in Storage
To protect treasures in storage, first of all use watertight, shockproof containers and stay away from carton boxes – they simply do not offer enough protection. Getting sturdy containers might seem like quite an investment, but it will be worth it. Besides severe natural disasters, they will also protect your collectibles from harmful day-to-day issues like humidity, leaking water etc. When you store your containers in the basement, do not keep them directly on the floor but place on sturdy, solidly secured shelves instead. Carefully wrap your items in bubble wrap or other padded material to further shockproof your treasures and/or use plastic bags for further waterproofing. Do note that the materials of some collectibles can deteriorate when kept sealed and airtight, so make sure you know how to care for them, like letting your items breathe every now and then.