We're not sure if it's the biggest house in the US. But it is the most expensive. This Bel Air Mansion with Car Collection is a brand-new, over-the-top build that includes absolutely everything. "Everything" encompassing more than just the four floors, 12 bedrooms, 21 bathrooms, three kitchens, massive home theater, and infinity pool with swim-up bar. It includes all the furniture, all the gadgets, all the wine, all the candy, the custom-built glass ping pong and billiards tables, shoes and balls for the bowling alley, and the helicopter. It even includes a $30 million car collection that features a custom Rolls-Royce and a Bugatti. And to help you take care of it all, it comes with seven full-time employees who live in their own "staff wing", ensuring that once you move in you won't need to lift a finger unless you want to.