DH gives you a free domain name for each account. That means you will get the first domain name for free.
Usually when you registered the domain name, they system will ask you how much you wanna pay. Did you see that page? If you still have the free domain, you will see something like "1 year - 0.00", "2 years - 9.95", and so on. From there, you can clearly tell how much you need to pay for the domain.
I'm not sure whether DH will refund you the money after you delete the domain. You may want to send a ticket to DH.
But I know DH will not refund you the free domain if you close your account.
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