Exceptional custom-built 2015 Colonial available for rent in desirable Mountainside, NJ, set on a generous 0.4-acre lot with a finished walk-out lower level, flexible guest space, and a beautifully designed multi-level backyard. A two-story foyer welcomes you in, with custom wainscoting, molding, high ceilings, quality craftsmanship, and abundant natural light throughout.The expansive chef's kitchen features an oversized granite island, custom cabinetry, pantry, and seamless flow into the family room with a gas fireplace. A formal dining room with coffered ceilings and a private living room, currently used as a home office, complete the first floor. The backyard offers multiple areas for dining, entertaining, relaxing, and play, including a Trex deck, patio, fully fenced yard, and expansive lawn. Upstairs, the luxurious primary suite features a spa-inspired bath and generous walk-in closet, complemented by spacious secondary bedrooms and convenient second-floor laundry. The newly completed walk-out lower level adds incredible flexibility with a private entrance, 9-foot ceilings, recreation room, custom wet bar, full bath, guest bedroom, and additional living space ideal for living, extended guests, or a private retreat.Ideally located near Deerfield School, parks, shopping, downtown Westfield, and convenient NYC transportation, this home offers the perfect balance of suburban tranquility, everyday comfort, and commuter convenience.