Deposited coins are stored in a coin storing device and change is paid out of coins storred in this storing device. For detecting an amount of coins going in and out of the coin storing device, a going-in-and-out detector is provided. For setting an initial amount P of stored coins in the coin storing device, an initial stored coin amount setter is provided. In an operation device, an operation for obtaining difference N between a current amount S of stored coins and the initial amount P in accordance with the output of the going-in-and-out detector and the initial amount P. When the amount of stored coins in the coin storing device is to coincide with the initial amount P (e.g., when an inventory operation is to be performed), a command device commands this. In response to this command, a payout control device performs, if the current amount S is larger than the initial amount P, control for paying out the number of coins corresponding to the difference N. Thus, if the current amount S of stored coins is larger than the initial amount P, a superfluous coin is automatically paid out so that the amount of stored coins is caused to coincide with the initial amount P. Conversely, if the current amount S of stored coins in the coin storing device is smaller than the initial amount P, a display control device displays that the amount of stored coins is short. The operator may additionally deposit deficient coins upon finding the deficiency whereupon the amount of stored coins is caused to coincide with a predetermined initial stored coin amount P.