Rarely available, extremely private single-story home situated in a highly desirable, close-to-town Costello Acres location. This almost 6000 sf estate/compound features a 6 bed, 5.5 bath main residence with attached, yet separate, 2 bed, 2 bath second residence set back on a perfectly flat and pristine ¾ acre lot. The main residence offers an inviting, yet understated exterior with an elegant traditional single-story floor plan and finishes. Architectural details include soaring cathedral ceilings, magnificent skylights, gleaming hardwood floors, beautiful built-ins. The luxurious home with formal living and dining, opening into a remodeled, light-filled kitchen with hardwood flooring throughout. This versatile layout with many options for working from home and entertaining friends and family. The majestic living room features cathedral ceilings, an elegant cast stone fireplace flanked by built-ins, and a french door slider to the deck. The gourmet kitchen features granite countertops, custom Alder cabinetry, multiple skylights, and a dining island in addition to an oversized dining area with built-in cabinetry. The alluring, light-filled master suite offers a sliding door to patio, a spacious walk-in closet, his and her sinks, and an inviting tiled shower. The main house also includes a large, home office retreat with a private side entrance, ideal for meeting clients at home. The second residence has a separate address and boasts an expansive kitchen, wood floors, a master bedroom with a walk-in closet, a second bedroom, an office, two baths, and a laundry room. This residence is ideal for extended family, hosting your Start-up, housing for Au Pair and offers separate parking, driveway, and street access on separately addressed 878 Campbell Ave. The lot itself is a coveted, park-like oasis in the heart of Silicon Valley, recently landscaped and ideal for entertaining, gardening, multiple play areas for children and features an expansive redwood deck, apricot orchard and lots of potential for a vineyard, stunning backyard pool or whatever you desire. One short block to top-rated Covington School with access to Blach Jr. High and Los Altos High. Prime location, close to Rancho, and a short walk to the village of Los Altos. Easy access to Foothill Expwy., 280, 85, Google, Apple, and all things tech. Bitcoin accepted.