Most mornings at Polk Manor, I woke up to the sound of seagulls. Or car break-ins. Or nothing at all. Living in a single room occupancy in the Tenderloin is actually a lot more quiet than you’d think. For about three years, I lived alone in a century-old 8-by-10 hotel room above a radical feminist bookstore, a cluttered storefront that sold sequined negligees and a massage parlor called Healing Winds that never seemed to be open. Had I not, I’d probably be a completely different person. Single room occupancies, or SROs, are maybe the last vestige of affordable housing in...