A mansion in Alpine, New Jersey, sold for $17.7 million last week. It topped 4 Stone Tower Drive's $16.7 million price tag from July 2024. The mansion also beat 15 Stone Tower Drive's $12 million mark set in January 2023. At 12 Rio Vista Drive, the property now stands as the most expensive sale in New Jersey's Multiple Listing Service in three years. The property stands out with its two indoor pools.