Errdome

I basically don't want to resell domains, (margins are ridiculously low) and it's additional headache , but what I want is to have customer add an existing domain to hosting package before he/she can buy the hosting. I've seen many do that but I can't figure out if WHMCs has that feature. I've unchecked "Allow clients to register or transfer domain" left only "allow clients to use their own domain" but the front page still offers domain registration which can be skipped but is still there.