In the fantastic area of Mountainside you’ll be in good company with around 6,897 residents with around 85% of those homeowners. With an average age of 52, the residents of Mountainside are fairly quiet and laid back, with many of them just about reaching retirement, or already retired. Many have downsized and picked Mountainside as their new home thanks to its peaceful and quiet environment. Over the past 30 days roughly 5 homes have been sold with an average sold price of $1,423,800. That is an increase of $246,299 from the previous period.