在你轉出之前，手續費會先顯示，看好再確認要轉出。
參考
https://support.coinbase.com/customer/portal/articles/2109597-buy-sell-bank-transfer-fees：
Transfers of virtual currency to an address off the Coinbase platform may incur network transaction fees, such as bitcoin miner’s fees, which Coinbase may pass through to you. Any such transfer fees will be disclosed to you at the time of the transaction.