Purchased: $25 million penthouse
Location: East 66th Street, New York, NY Time of Purchase: October 2011
Listed For Sale: $13.5 million home
Location: Allan Island, Anacortes, WA
The Microsoft co-founder's new Upper East Side pied-a-terre sits next to an 18-room unit he already owns, signifying he will likely combine the two units. The limestone building remains ultra-exclusive and houses other rich residents like oil billionaire Sid Bass. Allen is also trying to unload a virtually undeveloped 292-acre private island off the coast of Seattle, which first listed for $25 million in 2005.
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