When Lucy Sachs sublet her family's Amagansett mansion to Lee Hnetinka for a "family reunion," she had no idea the tech entrepreneur would actually use the luxe digs as a post-prom party pad for hundreds of teenagers.

Hnetinka -- the founder of tech startup Leetto and owner of Hamptons party-planning company Hamptons And Sons -- sublet Sachs' house from May 29 through June 26, 2012 for $30,000.

From The East Hampton Star:

“He told us he was going to have a family reunion here. He’s the smoothest-talking guy imaginable,” [Sachs] said.

The parties began right after Mr. Hnetinka’s company took over the property, according to Ms. Sachs. She came by the next day to drop off a document, “and there were two bedraggled teenagers in the kitchen. I asked, ‘What are you doing here?’ They just looked at me. I noticed that there were garbage bags with beer bottles, and the house was a mess.”

But, that didn't alert Sachs to how serious the problem was.

Then, at 5 in the morning on June 8, a neighbor called.

“He said, ‘I was awakened at 2:15 when party buses arrived with a disco ball, idling in the driveway. It sounded like the Hampton Jitney had arrived,’” [Sachs said.]

Around 100 students reportedly attended the party, where alcohol was served, on the weekend of June 8th, each paying $350 for three nights at the mansion. Hamptons and Sons had given each guest a manual of "party rules" which banned knives, guns and hard alcohol, amongst other things. After Sachs and the police broke up the party weekend, the teens were sent home.

And although initially promised a refund, an attorney for Hnetinka said there will actually be no refunds coming.

"I learned that he made almost $34,000 from that one weekend," Sachs told ABC.

This was not the only party that Hamptons and Sons and Mr. Hnetinka organized that weekend. Other parties, usually in celebration of prom or graduation, took place in Southampton, Sag Harbor, Noyac and other Hamptons locales.

Check out the house in Amagansett below:

All photos courtesy of Realtor.com

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