+1 to what Domaingel said. You can transfer it to another user if you sell it if they have an account at the same registrar, usually after 5 days of registering it at many registrars. Some will let you do it right after, but 5 days later is common.
If they want to use a different registrar then just have them buy it from you, transfer it to their account at that registrar and then after 60 days transfer it to whichever registrar they want.