One thing that may add to the costs is keeping track of and complying with the ever-changing state of the law.

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Starting up and running a business is fraught with enough uncertainty that it need not be further burdened by ever-changing city, county, state and federal fees, taxes and regulations.

WHITEHOUSE: Our Top Stories

Spend the day exploring the open-to-the public sections, such as the extravagant and glamorous State Apartments and the Drawings Gallery, with its ever-changing art exhibitions.

BBC: Five one-day bike trips from London