Question

II. HUMAN RELATIONS

B. Unjust Enrichment (Civil Code, arts. 22-23 and 2142-2143)

Analyze the following scenarios and determine whether unjust enrichment has occurred based on the provisions of the Civil Code:

1. Anna borrowed money from her friend Clara to start a small business. After a few months, Anna's business becomes successful and she earns a significant profit. However, Anna refuses to repay the money she borrowed from Clara, claiming that it was just a gift.
2. Mark, a homeowner, hires a contractor named John to renovate his house. They agree that the total cost of the renovations would be ₱500,000. During the renovation, Mark decides to make some changes to the original plan, resulting in additional work and expenses for John. Mark refuses to pay the additional amount, arguing that it was John's responsibility to anticipate and include these changes in the initial agreement.
3. Julia, a talented artist, mistakenly sold one of her valuable paintings to Alex for a significantly lower price than its actual worth. Upon realizing her mistake, Julia demands the painting back from Alex and offers to return the amount he paid. Alex refuses and insists on keeping the painting, claiming it was a fair transaction.
4. Mike discovers a valuable antique item in an old storage unit he purchased at an auction. He later finds out that the item originally belonged to Sarah, who had lost it years ago and is unaware of its current whereabouts. Despite knowing Sarah's ownership, Mike decides to keep the item for himself.