I've used LibraryThing for book boxes. Using smallish boxes (30-40 paperbacks each) so that carrying them is not a backbreaker. Scan the ISBN barcodes with phone app, fix old ones/whatever on web app, tag with box number written on at least two sides. No problems found so far.
I've used LibraryThing for book boxes. Using smallish boxes (30-40 paperbacks each) so that carrying them is not a backbreaker. Scan the ISBN barcodes with phone app, fix old ones/whatever on web app, tag with box number written on at least two sides. No problems found so far.