It's rude to sell things that belong to someone else.
Linda agrees to store some of her sister's furniture and other belongings in her house.
Linda wants to earn some extra money.
Linda and her sister agree on a moderate storage fee for the trouble.
Linda later claims ownership over the items and proceeds to sell them as she pleases.
Linda's sister is assured that her belongings will be store safely as they agreed.
Linda and her sister have a major dispute over who actually owned the items.