Ten documents, and most of them before a builder is appointed: a stage-by-stage plan, a contract checklist, a trade contact list, a condition report of the property, a project schedule, three purchase lists (kitchen, bathroom, electrical), a phase sign-off form and a snagging report. Kitchens, joinery and sanitaryware run 8 to 20 weeks, so the buying lists matter earlier than most people expect.

There is a particular kind of London flat that torments its owners. It has the bones, the ceiling height, the industrial windows, the sense that something extraordinary is lurking inside, and yet, every morning, it greets them with magnolia walls and laminate flooring. Potential, cruelly withheld.