Some of the richest people in the US, including billionaires Warren Buffett and Sam Zell, have made millions from trailer parks at the expense of the country's poorest people. Seeing their success, ordinary people from across the country are now trying to follow in their footsteps and become trailer park millionaires. The Guardian went to Orlando to learn the tricks of the trade from Frank Rolfe, the self-appointed dean of Mobile Home University, as he led would-be investors around a trailer park for sex offenders.