Best and most convenient way of handling multiple sites for different clients?

A very broad question, but how would you handle multiple domain names for different clients? Do you setup a "Web Hosting"-like server where you install Cpanel?

What are other cheaper alternatives to Cpanel?

You can choose to buy a "reseller" account from web hosting companies. This allows you to host multiple domains, each under different hosting account. Server management and technical support is done by the web hosting company without you having to worry about it. Each client has its own control panel.

I know Arvixe offers this by example. They provide cPanel for Linux hosting, and WebsitePanel for Windows hosting.

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