What is the bargain struck between me shiftlet and mrs crater over her daughter lucynell?

In Flannery O'Connor's "The Life You Save May Be Your Own," the bargain between Me. Shiftlet and Mrs. Crater involves him agreeing to marry her daughter, Lucynell, who is intellectually disabled, in exchange for a place to stay and a car. Mrs. Crater sees this as a way to secure a future for Lucynell, while Shiftlet is primarily motivated by his desire for the car and escape from his own circumstances. The arrangement ultimately highlights themes of exploitation and moral ambiguity, as Shiftlet's intentions are self-serving, leading to a tragic outcome.