PROBLEM TO BE SOLVED: To reduce the workload on a purchaser in a commodity sale at a locker device.SOLUTION: A server 50 comprises a communication unit 13 for receiving terminal detection information indicating that it is detected that a mobile terminal 10B is situated in a vicinity region by a position detection device 30 that detects the mobile terminal is situated in a region in the vicinity of a locker device 20 that comprises a locker part capable of accommodating commodities and is capable of opening the locker part by input of a key; and a control unit 11 for generating commodity purchase screen information of commodities accommodated in the locker device 20. In response to reception of the terminal detection information, the control unit 11 transmits the generated commodity purchase screen information to the mobile terminal 10B via the communication unit 13 to let the mobile terminal 10B display the commodity purchase screen information.
