4-bedroom house · SL7 1QE
For saleReduced £250k (−10%) on 15 SepListed 154 days
Opportunity summary
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About
One of Marlow’s most impressive contemporary homes, in one of the town’s most desirable addresses: Formosa is a truly exceptional house situated on an island within the Thames, accessible only on foot.
Designed by Baca Architects, the house is the UK’s first amphibious home and has previously featured on Grand Designs.
It sits on the riverbank on fixed foundations, but should ever a flood occur, it rises up in its own wet dock and floats, buoyed by the floodwaters.
This ground-breaking technology makes for a totally unique property, which is also supported by high levels of insulation, low energy systems, high performance windows and a biodigester drainage system.
It’s a house for the future, with excellent green credentials. Externally the beautifully landscaped gardens reflect the building’s setting in a conservation area.
From the house there is excellent access into Marlow town via the footbridge, and lovely views across the river towards Winter Hill. Marlow is also renowned for its access to high quality schooling.
The house is as striking internally as it is from the outside, with sharp angles, clean lines and vast glazed windows.
Neutral walls provide a visually quiet backdrop, allowing the stunning views to remain the focus.
Engineered wood floors nod to the natural world outside, further enhanced by the wall of floor-to-ceiling bifold doors at the back of the house that bring the outside in.
On the ground floor there are two bedrooms at the front of the house (one en suite), with the main living space at the rear to maximise the panoramas over the river and beyond.
The main reception room incorporates a number of zones in one generous room: A stunning fitted kitchen, a dining nook and a sitting area in front of the outdoor terrace.
A modern glass panelled staircase leads down to a further reception room/cinema room, a further double bedroom, shower room and a utility room, and up to a principal suite that occupies the entire first floor with a sizeable bedroom, dressing room, and spa-like bathroom with a steam room/sauna.
Outside Formosa is situated on Lock Island, which can be accessed only by the pedestrian walkway across Marlow Lock making it one of Marlow’s most exclusive and private addresses.
A key benefit of the island is it is a very safe place to live or bring up children. The wildlife is amazing and residents feel the river is an extension to their gardens.
The raised riverside decking and integral pergola provide a 'virtual' room to take in the river and garden views.
Native and international plants, raised borders, and two terraces surround a peaceful river lawn.
At the front, an impressive Torii Arch draws the visitors along a path between elegant shrubs to the elevated front door.
Situation Lock Island offers a rare sense of seclusion in the heart of the river Thames at Marlow.
Accessed via a footbridge, the island immediately feels removed from the everyday, creating a quiet threshold between the town’s refined bustle and a more peaceful, enclosed riverside setting.
Despite its central location, it carries a strong sense of privacy and exclusivity.
As a location, it offers a rare combination of central Marlow convenience with an unusually private, almost retreat-like riverside character.
Lock Island is located by Mill Road to the east of Marlow town centre, ideally located for the High Street and the station, in addition to the Thames Path following the river.
The property is located a 0.7 mile from Marlow town centre with its excellent range of shopping, boutiques, bars and restaurants.
A key attraction of Marlow is also the high quality of schooling, including Sir William Borlase’s Grammar, Great Marlow School and Danesfield Primary school.
The Marlow bypass (A404) connect to both the M40 and M4 motorway networks, and local rail services at Marlow connect to London Paddington via Maidenhead and the new Elizabeth line service.
Marlow offers many outdoor pursuits including rowing and equestrian facilities, cycling, river and countryside walks in the glorious rolling countryside of the aonb.
The Prime team would be delighted to show you around this property. Property Ref Number: Ham-65217 Additional Information Local Authority Wycombe Council. Council tax band H.
Services Mains electricity is supplied to the property. Water via borehole. Private drainage via macerator/biodigester.
Value & comps
No previous sales on record.
Returns
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Archie refurb estimate: a Pro feature
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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
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FAQ
About Formosa, Lock Island, Marlow
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