A computer system receives, from a client device, a virtual bill request including user identification information of a user associated with the client device and then activates a virtual bill and associates the virtual bill with the client device, the virtual bill having a predefined effective time period. After receiving data corresponding to one or more items added to the virtual bill within the predefined effective time period through respective close proximity data communication between the client device and one or more respective terminals, the computer system determines a value based on the data corresponding to the one or more items and sends a verification request to the client device. Upon receipt of verification information responsive to the verification request, the computer system initiates a transfer of the value from an account associated with the user in accordance with a determination that the verification information is valid.