[13] Aged 9 when Christodoulou found refuge in the UK, his father declined a council flat, forgoing the security of a lifelong tenancy for renting in a safer neighbourhood to protect him.

[15] He began his business career in Hatton Garden, starting off as a diamond mounter[16] and then persuading the landlord of a small jewellers to allow him to occupy a workshop by accepting cut-price jewellery repairs as a form of rental income.

[25] In October 2021, Christodoulou had been set to take over Cypriot professional football club Omonia Nicosia from current major stakeholder Stavros Papastavrou, a New York-based Cypriot investor, in a £30 million deal, but talks reportedly broke down over the issue of him having to sell the shares on to Omonia fans after five years, one of at least two clauses in the original management deal with Papastavrou that Christodoulou had sought to scrub.

[12] The property entrepreneur is also dyslexic and accordingly has a preference for making business decisions over the phone, an in-house solicitor for Yianis Group has told London's High Court.

[37] In November 2023, Christodoulou was awarded by the Cypriot government for his charitable work and for his efforts to promote Cyprus abroad during a ceremony in London at the World Travel Market conference.

Inspired by his own childhood, displaced from his homeland as a child, in 2016 he founded the Yianis Christodoulou Foundation (YCF),[40] which seeks to support disadvantaged children and their families in the UK and abroad, with a special focus on poverty alleviation and education.

[42] In July 2021, Christodoulou sailed Zeus to Cyprus where the Foundation raised €365,000 to support the island country's disadvantaged children as well as local schools destroyed by wildfires.

[14] The Foundation backed King Charles III, then heir apparent to the British throne as Prince of Wales, at a charity event in Dumfries House, in Ayrshire, Scotland.

[46] In 2021, Christodoulou stood alongside Monaco ruler Prince Albert as he opened a new gym facility for staff of the Princess Grace Hospital Centre which had been built and paid for by the Foundation.

[47] During the pandemic on Cypriot Labor Day "Thank You" snack parcels were delivered to all 9 public hospitals in Cyprus to more than six thousand doctors, nurses and other health care workers from the Christodoulou's foundation.

"[3] This is a reference to Canary Riverside, where Christodoulou was stripped of day-to-day management control over the property in October 2016, with a professional court appointee installed to act in the best interests of the site.

Leaseholders were able to prove fault against CREM, a subsidiary company,[51][52][53] that they had suffered over many years due to poor management of the estate, in particular a lack of transparency surrounding how their money was being used.

[57] In 2022, it was reported that Christodoulou had admitted before a tribunal that he had overcharged the 1 West India Quay flat owners by 26% on utilities, wrongly adding commercial rate VAT and a climate change levy to their bills for heating, cooling and hot water.

[58] Christodoulou has also been named in parliament, with former MP for Poplar and Limehouse Jim Fitzpatrick claiming that the litigation and threats faced by the court-appointed manager at Canary Riverside are "little short of harassment".

[59] A former secretary of the 1 West India Quay residents' association has been subjected to a defamation threat by Christodoulou's lawyers, as have more than 100 leaseholders at neighbouring Canary Riverside.

[55] In July 2018, his lawyers unsuccessfully sought to prevent the then local MP, Jim Fitzpatrick, from raising the case of Canary Riverside in parliament.

The renters are said to have been told by the lettings agent, acting on behalf of the three corporate landlords all "majority owned" by Christodoulou, that the request was "unreasonable" and "unrealistic".

[66][67] On 9 November 2020, former shadow home secretary Diane Abbott tabled an early day motion in parliament urging John Christodoulou to negotiate "fair and reasonable rent adjustments" with affected tenants in Somerford Grove.

[71] In August 2022, the Upper Tribunal in a different case ordered that Mr Christodoulou's landlord company at Canary Riverside, Riverside CREM 3 Limited, pay £67,000 towards the legal costs of the independent court-appointed manager and the leaseholders at the site for its "unreasonable" conduct, having instigated a meritless appeal to the Upper Tribunal while conducting the appeal in a manner that was also deemed unreasonable, inexplicably advancing a new legal point at a very late stage in the proceedings that should have been used in the original case, if used at all.

[72] In the appeal hearing, the landlord was reportedly admonished by Deputy Chamber President Judge Martin Rodger KC for an "extremely unattractive" approach to tribunal.

[75] In October 2021, The Times newspaper reported that the low-profile billionaire property tycoon had covertly claimed millions of furlough money from the taxpayer despite telling a London audience that he was self-reliant through the crisis and criticising those businesses which did need government assistance.

In December 2022, a property tribunal ruled in the Canary Riverside case that John Christodoulou landlord companies, CREM and Octagon, misappropriated approximately £1.6 million in secret insurance commissions from flat owners.

The decision was reported in the Financial Times as a "rare victory in service charges" for UK leaseholders, a development it suggested lends support to a recent warning by the FCA that freeholders, managing agents and brokers "may be selecting insurance policies that maximize their own remuneration . . .

In March 2024, the UK government and Michael Gove, the then Secretary of State, commenced legal action against Christodoulou's companies to pay £20.5 million towards remediation of the unsafe blocks of flats they own at Canary Riverside in London Docklands.