Shelf locations
Save the location with your copy, along with condition, purchase details, and notes.
Living room, top shelf. Study, by the window. Give each copy a location that makes sense in your home.
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Save the location with your copy, along with condition, purchase details, and notes.
Photograph the book you own when the catalog cover is not the right one.
Export book details, notes, and saved cover photos. Keep a copy in Files or iCloud Drive.

Export a library backup from Settings. Importing adds missing copies while leaving existing records unchanged. The support page has more guidance on backups and iCloud.
Backup and iCloud help