Look around before you spring for the one from Williams. Single faucet kegorators are going for closer to $500 with the taps & towers. My Nostalgia Electric (don't think you can find them any longer) was under $500 and I had a triple tower from my last kegorator that crapped out.
Search kegorator at Amazon or Google shopping to get an idea. You will need to change connections for units designed for commercial beer kegs of course.
Look at Craigslist and Marketplace for used too. Sometimes you can find a commercial grade kegorator from a bar/restaurant.