Joe Girard’s Keys

Origin
Joe Girard is an American salesman known for selling a total of 13,001 Chevrolets between 1963 and 1978, averaging six cars sold a day. He achieved this by sending 13 cards a year to all clients and potentials; one each month and one for Christmas. He also kept in touch with people, sending them thank you notes and free goodies, earning his average daily sell of six cars that way.

Effects
His keys give a holder who needed to sell something beforehand the ability to do just that. They can do this the same way Girard did or come up with their own schemes; each deal is not exactly the same, as are the methods the person employs. The only real downside is that the person soon after a sale suffers physical exhaustion and tiredness.