what is the importance of money in the play death of a salesman?

Wily believes in the "American Dream". Money is an important byproduct of that dream but it is wrapped up in illusions of success, validation and contentment. Willy is fixated on superficial aspects of personal success. He thinks that with the right looks, friends and personality success is deserved. Part of that success includes money but much of it has to do with his own external and internal validation. Willy craves to be seen as successful and money is the trappings of success. I guess you could say that money is one of mant symbols of sccess that Willy is looking for.