If there is a Bishop in the active party, they can appraise unidentified items in the bag free of charge. This is a good method to earn money, and restock the Jadgebol's Shoppe.
However, the success of the item being appraised is proportional to the Bishop's level. If the Bishop fails the attempt to identify an item, they might suffer from the frightened condition -- being unable to appraise that or any other item until the status ailment goes away, or occasionally not attacking during battles.
Identify is accessible in Dondun's Tavern and the Camp menu.
Alternately, items can be identified for a fee in the Jadgebol Shoppe. However, the amount of money the party will pay to identify the item is the same that the shop will offer in exchange for it, making selling items identified without a Bishop completely unprofitable.