3-bedroom flat · W1W 6DB
For saleListed 14 days
Opportunity summary
See Archie’s verdict, returns by strategy and what to check before viewing.
About
London's mansion blocks were the city's answer to Paris's renowned apartment living.
They offered well-to-do families an alternative to the townhouse, with all the space, ceiling heights and grandeur they expected, arranged laterally across a single floor.
Constructed in the mid-1920s on the Howard de Walden Estate as a building of superior apartments, the highest grade of the day, Stone House was developed by a syndicate that included Charles Peczenik, who trained in Paris under René Sergent, the architect behind the extension and refurbishment of both Claridge's and the Savoy.
The building's architect, George Vernon, gave it a rusticated stone ground floor, arched windows and a corner tower that anchors the junction of Weymouth Street and Hallam Street, within the Harley Street Conservation Area.
Set on the raised ground floor, a grand Marylebone apartment with ceilings of almost ten feet.
An open-plan reception room incorporates space for dining, a fully fitted kitchen and enjoys a double aspect onto both Weymouth Street and Hallam Street.
A walk of approximately half a mile takes you up Portland Place, past John Nash's Park Crescent and into The Regent's Park itself.
Exceptionally well served for the best that Marylebone has to offer: The Royal Academy of Music, Bechstein Hall, Wigmore Hall and five Michelin-starred restaurants all lie within half a mile, with Great Portland Street and Regent's Park stations both within 0.3 miles.
Value & comps
No previous sales on record.
Returns
Set an offer; the calculator follows it.
We're still gathering serviced-accommodation data for this area.
Archie refurb estimate: a Pro feature
0.0% below asking
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Deal
Properties like this can earn 2–3x BTL yields when converted to HMO, with retrofit costs around £10k/room. Sign in to see the full tier, yield projection, and cost breakdown.
Commercial properties like this can earn 30-50% higher yields when converted to residential under Class MA / Q / P / PA, with prior approval costing ~GBP 96/unit. Sign in to see the recommended route, yield uplift, and cost breakdown.
BRRR-suited properties can recycle 80-100% of investor capital on refi, leaving a high-yielding rental with most of the money out. Sign in to see the refurb cost stack, ARV projection, and refinance maths.
Detached + large garden = sub-division play. Pro tier unlocks the tier badge, plot size, uplift estimate, and regional land benchmark.
Short-lease flats trade at deep discount, but extending under the 1993 Act often costs far less than the discount. Pro tier unlocks the tier badge, premium breakdown, long-lease ARV and arbitrage maths.
See projected short-stay revenue vs a vanilla BTL for this property.
See real sub-let margins (HMO room rates & SA nightly rates) vs the landlord rent.
Area
Agent & docs
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FAQ
About 9, Weymouth Street, London
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