A new public awareness campaign challenging people to live on just £3 of food a day has, on the surface, nothing to do with property. It is designed to build empathy for households facing food insecurity, a growing problem as inflationary pressure squeezes disposable incomes. But for landlords, letting agents and mortgage lenders, the campaign is a useful, if uncomfortable, proxy for a much bigger story: the shrinking margin many UK households now have between essential spending and housing costs. When food budgets are cut to the bone, rent and mortgage payments are rarely far behind in the queue of financial casualties.