The grounds encompass two guest houses, a tennis court, several greenhouses, a tree house, rose and vegetable gardens, and a second hidden driveway entrance onto the property.

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Meanwhile, Oakland Tribune columnist Daniel Borenstein notes that his city has levied what he calls a "hidden pension tax" on property owners for decades to pay off a municipal pension fund that went bust in 1976.

WSJ: Steven Malanga: How Retirement Benefits May Sink the States

Police searched his property and found a tin box hidden in a hedgerow with documents linking Castle to various offences and victims.

BBC: Kevin Castle

"It shines a light onto previously hidden relationships, uncovering anomalies between such elements as bank interest, property income and lifestyle indicators before homing in on unexplained inconsistencies, " an HMRC spokesman said.

BBC: Tax form

"New World's stock price has jumped 100% in six months primarily because people are now seeing the hidden value that management is unlocking, " says Michael Green, property analyst at Nomura Research Institute.

CNN: UST A FEW YEARS

This is no accident: the place was built from the ground up to be the best, with no expense spared, including extensive hidden underground tunnels so you never see maids or room service staff walking around the low rise, spread out property.

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