Despite owning four plots of land in Chester, South Carolina, since 2022, Gilgo Beach serial killer suspect Rex Heuermann is unknown to at least four neighbors who live on the same street as his lots.

Neighbors are, however, familiar with Rex's brother, Craig Heuermann, who has lived in a ramshackle home surrounded by no trespassing signs for about two decades on the same street where Rex purchased land last year, possibly in preparation for his retirement.

On Tuesday, New York State Police, with assistance from the FBI and the Chester County Sheriff's Office, went to Craig's lot to seize a green Chevy Avalanche connected to Rex and the Gilgo Beach murders investigation. The Heuermanns' properties have remained quiet since then.

Four neighbors who spoke with Fox News Digital do not encounter Craig often, but on the rare occasion he does leave his house and talk to neighbors, he usually comes off as a bit odd, they said.

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One neighbor described Craig as a "doomsday prepper," saying his yard is full of junk, but it never leaves his property line. Photos of Craig's property beside his home show garbage bags, empty Amazon boxes, what appears to be a woodworking station and a pile of wooden slats. 

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Rex Heuermann, an architect, said in a recent YouTube video that he enjoys woodworking — a hobby he learned from his father, an aerospace engineer who had a woodworking workshop at the Long Island home Rex lived in before his arrest last week.

"[W]e rarely see him outside. He does have a ton of dogs on the property that you can hear barking all the time, but they don't really bother us," one neighbor said. "But as far as our few interactions, they've always been pleasant."

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He did apparently hear Craig "yelling obscenities one evening at someone, calling her a ‘whore' and some other words, but we didn't get involved," the neighbor said.

Craig's front gate has two signs. One says, "Keep out/No trespassing," the other says, "No Warrant/No Entry." Neighbors described hearing dogs, loud music and banging from his lot.

Rex's properties are undeveloped and back up to a series of small, connected lakes on which some residents keep boats.

Craig has one rule, according to two neighbors: "Don't cut the grass on Sunday."

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One neighbor said he learned the hard way that Craig enforces this rule when he went to cut grass on Sunday at the property across from Craig, which he used to own. Craig allegedly approached the neighbor from behind and hit him over the head with a "steel pole."

"Out of nowhere," the neighbor recalled. "I called the police because I was going to shoot him, but my wife talked me out of it. We called the police, and when we talked to [Craig], he said, ‘Well, I told him not to cut grass on Sunday.’"

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Craig also handed out business cards to people on his street that include his name followed by the words, "Bad Motherf-----," and his phone number.

Craig Heuermann could not be reached for comment for this story.

"I keep my distance. … I think he's as crazy as a bed bug," said a third neighbor, adding, however, that he has never had any real issues with Craig. 

Craig even found one neighbor's runaway dog once and brought it to a nearby vet.

A fourth neighbor whose house sits between Rex's and Craig's properties said he has run into Craig only a handful of times and has never seen Rex. The neighbor said he has not had any issues with Craig other than one time when Craig asked him about some items missing from his property, which the neighbor said he knew nothing about.

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Craig has not been charged with any crimes related to the Gilgo Beach murders. His brother, a resident of Massapequa Park, New York, faces charges of three counts of first-degree murder and three counts of second-degree murder in the slayings of three women – Melissa Barthelemy, Megan Waterman and Amber Costello – whose remains were discovered near Gilgo Beach in 2010. He is also suspected of killing Maureen Brainard-Barnes, whose remains were also found there.

Authorities said the three victims Rex allegedly targeted were sex workers who advertised online .

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The slayings have remained unsolved for more than a decade after the search for missing escort Shannan Gilbert, 24, first led police to the bodies of young sex workers and other victims along the Long Island shore.

The suspect was tied to the crimes through DNA evidence and cellphone data. Rex Heuermann allegedly called at least one victim's family after her death and taunted them, according to court documents.

Authorities have been searching Rex's Long Island home for evidence. It is unclear if police will also search his South Carolina properties.