Source: The Great Interpretation of Dreams (Ibn Sirin)
Seeing one's deceased neighbor in a dream indicates a change in the dreamer's fortune. If happy, his fortune improves; if sad, his fortune worsens.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
Seeing one's deceased neighbor alive indicates goodness coming from the neighbors.
Source: Signs in the Science of Expressions (Ibn Shaheen)
Seeing one's deceased neighbor is interpreted as goodness if he is in a good state.