A bank temporarily housed in a mobile home while a new building is built, looks like an easy target to break into. On the other hand, why not steal the whole bank, and rob it in a safer location.
Bank Shot is a 1974 American heist comedy film directed by Gower Champion and written by Wendell Mayes. It was loosely based upon Donald E. Westlake's 1972 novel of the same name, which was the second book of his "Dortmunder" series. The film stars George C. Scott, Joanna Cassidy, Sorrell Booke, and G. Wood.