I'd recommend you stay away from that altogether.
Lots of these companies end up holding your domain hostage if you ever want to move it. Or, if you cancel their other services, they charge you a large penalty to get your domain. And they may hold the domain in their own name, so if they ever go out of business, you would lose your domain.
Domains are cheap enough that it's well worth your while to buy them from reputable registrars.