If you park in their ramp and make a purchase on the wharf take that receipt to the payout and you will get a discount on parking. First half hour free
If you park in the garage you will get a card/ticket on entry. Once parked come up the stairs or out the elevator to main level. On the main level you'll find the ticket payment machines and attendant usually. If you make purchases at wharf bring the receipt to attendant for a discount on parking. You'll receive a discount ticket to feed in the machine after you place your original ticket in it. You may then pay the balance and go down to your car to exit.
Not sure what a Wharf card is
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