If you wanted to setup a dedicated server for someone in need of one, have it colocated with a datacenter and charge the person your selling it to whatever they are willing to pay,, how could you monitor the server, but still leave them in complete control with root access and you not need root access?

Are there any panels that allow you do monitor and ultimately control the root user, in other words lets say they didnt pay, i would need to cut the root user off and assign a new one after reselling...

How could something like this be done?

Well, if you HAD to get root access for something like that, why not restart the server and assign a new pass too it? If you need to resell it, you would reinstall the software anyway, so no big deal there.

Yes, but i would like to be in control in the background, while they are root access...

can that be done..

Are there any panels that allow this, and allow you to setup dedicated servers etc on a network under one control panel.

There's only one super user. You can't limit access to one and not the other. You may as well share the access and account. Anything else would be pointless.

If you don't own the datacenter yourself, or can't get 24/7 access to it, you'd probably be better off setting up a seperate account with root level access for the user/client. With it properly setup all the user has to do is issue sudo to get full root access and this still leaves you full control.

sudo is not intended to allow another user full root access. Just share the root account, I don't see the point or reason for setting up anything else. Setting up another account to use the uid/gid 0, will just cause problems and confusion or make the guy renting the server think it's been compromised. Just tell them the conditions about it and why. If you have a good reason, they should be okay with it. Anything else will just upset them if they wouldn't agree to it anyway and pose hassles or other problems and would just be pointless anyway.