The wealthiest, flashiest people I’ve ever met were at Mill Hill, where I went for secondary school – and I’ve never encountered anything like it since. I spent my teenage years going every day to this huge campus, in a peaceful, leafy, village-like suburb of north London, with expansive, beautiful grounds and Greco-Roman architecture. In 2026, it costs £10,000 a term – or £18k if you’re a full-time boarder. It hasn’t got the old-school poshness of somewhere like Eton, with hundreds of years of generational wealth, and it isn’t especially academically selective – it ranked 43rd of London’s private schools...