The top 10 richest neighborhoods in Los Angeles County, with their mean household income: Beverly Hills (the 90120 section): $395,734. Hidden Hills: $383,731. Rolling Hills: $373,524. Bel-Air Estates: $355,007. Upper Laurel Canyon: $332,037. Brentwood Park: $324,289. Coldwater Canyon: $323,929. Brentwood Heights: $321,933.