Fraser Bond are the leading lettings and property management agents for OneTwentyFour Marylebone - London W1H. OneTwentyFour Marylebone residential development in Marylebone, London W1, completed in 2017. The development comprises 12 luxury flats including two gorgeous open plan duplex penthouses with generous terrace space and views across west London.[2] 2015 March - Westminster City Council grants planning permission for demolition of existing buildings and erection of new building on basement to fourth floors with rooftop plant enclosure; new rear lightwells/railings on Walmer Place; creation of.