Peter Apps’ first book was an award-winning investigation into the causes and consequences of the 2017 Grenfell Tower high-rise fire in London. His second book, Homesick, begins with the basic unit of the housing crisis: a bedsit (a studio apartment, maybe with a shared kitchen or toilet) in a cramped building, with “whitewashed walls, numbered doors with individual locks, fire-exit signs and emergency lighting.” There is mold.