NEW YORK—A Long Island, N.Y., family thought they got a good deal when they found a rental house for $1,000 a month—until the owner showed up and asked what they were doing there.

Nassau County police arrested Gregory Garvin on Wednesday for posing as a real estate agent and renting out the house in the hamlet of Roosevelt. Garvin was charged with grand larceny and fraud.

Police say Garvin also collected a $1,000 security deposit from the couple.

The family was living in the house about two weeks when the real owner showed up.

Police say the house had been vacant and the real owner had planned to sell it.

The District Attorney’s office says the name of Garvin’s attorney is not yet on record.