There is no upper or lower limit. You can exchange as little as one bill for each currency. And the daily amount of foreign currency exchange transactions by the same person is limited to 500,000 yen per day.
USD：BUY ¥143.78/SELL ¥139.20
EUR：BUY ¥160.28/SELL ¥155.25
GBP：BUY ¥192.29/SELL ¥178.50
CNY：BUY ¥21.24/SELL ¥18.40
HKD：BUY ¥19.33/SELL ¥16.90
KRW：BUY ¥0.1184/SELL ¥0.0930
PHP：BUY ¥2.82/SELL ¥2.25
SGD：BUY ¥113.03/SELL ¥105.30
THB：BUY ¥4.72/SELL ¥3.90
CAD：BUY ¥107.16/SELL ¥98.00
AUD：BUY ¥100.61/SELL ¥88.35
NZD：BUY ¥93.01/SELL ¥82.12
TWD：BUY ¥4.89/SELL ¥4.01
CHF：BUY ¥170.50/SELL ¥163.06
MYR：BUY ¥37.79/SELL ¥29.86
VND：BUY ¥0.01/SELL ¥0.005