The Dower House Mystery by Patricia Wentworth, for the #1925Club

Amabel Grey, a young widow living on a tiny income, is anguished when her daughter Daphne demands £200 so she can travel with friends to Egypt. She simply doesn’t have it. But when she visits her lawyer, she overhears an old acquaintance, Mr. George Forsham, complaining that three sets of tenants have left the Dower House he owns, claiming it was haunted. He asks the lawyer to find a caretaker who will stay for six months and, after he storms out, Amabel takes on the assignment, securing payment in advance.