A Waterfront House with the Message ‘All or Nothing at All’

This article is part of our Design special section about water as a source of creativity.

Consider the 21 gilded mirrors lining the music room, each more extravagant than the last. Or the Italian monastery table that seats 24, never mind the tapestries, peacock feathers, brass candlesticks and Persian rugs seemingly everywhere.

And did we mention entire suites dedicated to Frank Sinatra and Noël Coward?

Let others embrace minimalism. Good things come in multiples in the waterfront home that Tom Postilio and Mickey Conlon have created for themselves on two and a quarter acres on the North Shore of Long Island.

Even the house itself, which began life as a single-story Mediterranean-style abode from the 1960s, appears to have adopted the more-is-more mantra, swelling to 10,000 square feet of Spanish Colonial splendor encompassing six bedrooms, five fireplaces, a conservatory, a library and an expansive subterranean level with a screening room, music “archive” and hammered-brass bar presided over by an Al Hirschfeld mural and a portrait of Charles Nelson Riley — on black velvet.

“Too much of a good thing is wonderful,” said Mr. Postilio, quoting Mae West by way of Liberace.

The whole enterprise began modestly, though.

Mr. Postilio, 54, and Mr. Conlon, 47, real estate brokers with a background in show business and a celebrity clientele (including Liza Minnelli, Barry Manilow and Marilyn Horne), had long had a one-bedroom apartment in Manhattan and wanted a place they could escape to on weekends.