This is the reverse of a rags-to-riches story. This is a riches-to-rags story.”

That’s the bemused voice of time-share entrepreneur and one-time billionaire David Siegel, who with his flamboyantly blond wife, Jackie, forms the spellbinding center of “The Queen of Versailles.” Lauren Greenfield’s documentary about the Siegels began as a chronicle of their profligate nouveau-riche lifestyle and their construction of America’s largest home — a 90,000-square-foot pile near Orlando, Fla., unironically called Versailles.

But as Greenfield was filming David (age 74 in the film), Jackie (30 years his junior) and their sprawling family of eight children, devoted staff, countless animals and myriad friends and hangers-on, the financial meltdown intervened. What might have been a meditation on wealth, greed and consumerism became something else entirely.

“The Queen of Versailles” turns out to be a portrait — appalling, absorbing and improbably affecting — of how, even within a system seemingly designed to ensure that the rich get richer, sometimes the rich get poorer.

Of course, everything’s relative. As “The Queen of Versailles” makes clear, at the height of David’s fortune, he and Jackie took the term “living large” to its most literal extreme, decking out their Florida home in gilded geegaws that manage to look tacky even if they are priceless antiques.

When Jackie gives a friend a tour of the construction site of the new house — which was supposed to have 13 bedrooms, 30 bathrooms and 11 kitchens — the friend initially mistakes Jackie’s closet for a bedroom. Later, when David’s company, Westgate Resorts, experiences a credit crunch and bankruptcy looms, his buxom wife is forced to fly commercial — a brand-new world for her