You can open a saving account for saving your US$ because the rate of interest is higher than chequing account. And also open a chequing account. This kind of account is fexiable. You can withdraw and deposit your money easily and open a cheque to others. Generally, it is not service fee if your balance in your account keeps above CAN$1000.00. For credit card, if the limit is $1000, it doesn't mean you can just use 1000.00. You can save money into your credit card account(It is other kind of account) , for example, 1000.00. Of course you can spend 2000 using your credit card. Hope that the above is helpful for you.