Castellane is the private channel to the most significant residences on the Pacific. Malibu, Bel-Air, Montecito, Laguna. Placed quietly, completely, once.
We do not sell square footage. We place a rare few inside the homes that define a coastline — with discretion, with patience, and entirely on their terms.
110 feet of glass frontage, a vanishing edge, and nothing between you and the horizon.
A cantilevered staircase under a falling-water chandelier, framed by a two-storey wall of glass.
A monolithic island, disappearing glass doors, and the sun setting straight into the room.
Double-height volume, a stone hearth, and a horizon line that does the decorating.
A sunken lounge around an open fire, the outdoor kitchen behind, the ocean below.
The most significant homes never reach a portal. We move within a private network of owners, architects, and family offices.
One advisor, one client, complete confidentiality. Your search and your sale stay between us.
We represent homes that matter — designed, sited, and built to a standard the market rarely sees.
Qualified principals across New York, London, Geneva, and the Gulf, introduced only when the fit is right.
Cinematic films, private viewings, and quiet placement. Visibility on your terms, never the open market's.
Legal, design, staging, and relocation handled end to end, so the keys change hands without friction.
A full global launch for a single, significant home.
Private membership. See the coast before it lists.
We source, vet, and negotiate the home you cannot find.
Engagements are accepted selectively. Castellane represents a limited number of clients and residences at any time to protect discretion and outcome. Figures shown are indicative; terms are confirmed in a private engagement letter.
"A great house is not a transaction. It is the stage for the next chapter of someone's life. My only job is to make sure the right person walks onto it."
Sienna Castellane founded the practice in 2009 after a decade representing trophy estates from Malibu to Montecito. She works by referral, takes a deliberately small book, and is known for closing the homes others could not.
Her clients are founders, principals, and families who value privacy as much as the view. Most never meet another agent.
Tell us what you are looking for, or what you may consider selling. Every inquiry is read by Sienna directly and answered within one business day.
This is a concept site — a fictional luxury brand, designed and built end to end in code by Real Brand. No page builders, no templates. The motion, the 3D dust, the scroll-driven film, the type, the price counters: all hand-built. We made it to show one thing — what your business could look like with this much care behind it.
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