What is the best way to grant website or application administrators access to their own resources?

I am learning how to setup a shared hosting web server.

As a server administrator whose the highest access level in the server, I want to grant my friends as site administrators access to their own sites.

The question is: What is the best way to setup their accounts and what level of access should be granted to them?

Edit 1:

I want them to have remote access to their own resources using IIS Manager. By this way, I can mimic a real shared-hosting ser开发者_开发问答ver.

You can install a FTP server. And assign the permission to access a folder for a user with user name and password.

Use the delegated administration on IIS.