I'm selling my Xbox 360 premium, however, I have sold the 20GB hard drive elsewhere.
As you can see from the picture, it currently has 4 red rings. I turned it on yesterday and it had the 3 rings of death so I think 4 rings is showing because I have not plugged in the AV cable correctly.
It comes with the official power source and AV/HD cable.
There are many repair guides out that feature true HD video files, free updates, 24/7 customer service centres and far easier repair methods that will have you gaming again but I do not have the time to do this.
It is sold as used - a few marks but nothing to put you off.
Any questions just ask.