Love Insurance (version 2) by Earl Derr Biggers (1884 - 1933)

On duty with Lloyds of London in NYC, young Richard Minot is sent to the St Augustine-ish town of San Marco to ensure that a wealthy young lady, Cynthia Meyrick marry his firm's client, Lord Harrowby. Then, in a meet-cute on a slow-moving train, Minot meets the very enticing Miss Meyrick and... reconsiders his duty. - Summary by Matt Pierard