By Darran Simon CNN

SPARTANBURG, South Carolina (CNN) -- Daren Owens recalls how Todd Kohlhepp sold three homes for him, including one on the day it listed.

Kohlhepp was an attentive real estate agent, calling Owens "boss" and "sir" in text messages. He was chatty, not threatening, Owens said.

About three months after Owens' final sale -- a 5-bedroom house with a jacuzzi -- the Boiling Springs, South Carolina, resident and his family learned that his realtor had confessed to killing four people and is a suspected serial killer.

"We were like 'wow, we know this guy,'" said Owens, 49, "This feels kind of strange having that kind of person sitting at your kitchen table, walking through your house, and the idea that during that whole time, he's got keys to our house and could've gotten in at any time is just very nerve-racking."

In nearby Spartanburg, Kohlhepp's hometown, his name was known to many because it was posted on front-yard For Sale signs across the city. Those who didn't know the name before know it now that police say Kohlhepp may be responsible for seven deaths.

Residents' reactions to news that bodies were found buried on Kohlhepp's farm range from shock to disbelief and disgust that a serial killer may have been living in their midst. Some people said they had either crossed paths with Kohlhepp in person or on social media, or know someone for whom he sold a home.

"It's really disturbing to know that somebody like him .... a serial killer, was living among us," said Lola Marzouca of Spartanburg. "You would never think he would be capable of something like that."

'There will be consequences'

Deanne Blackwell, 31 of Spartanburg, has known Kohlhepp casually for more than a decade.

In March, a private message she said Kohlhepp sent her on Facebook -- one of several messages that went unanswered -- seemed harmless.

It read: "woman. you better talk to me more... or there will be consequences ... not sure what they will be, but I will pout," according to a screen grab of the message she said came from Kohlhepp's account.

It's impossible to discern what Kohlhepp meant by "consequences," but Blackwell said knowing what she does now about the killings, it spooks her.

"Now I think about it, yes, I'm completely creeped out because of everything after the fact," she said Thursday in a phone interview.

Lauren Duncan, 27, who is Marzouca's co-worker at a car dealership in Moore, 12 miles south of Spartanburg, said she recognized Kohlhepp's name from a sign in a former neighbor's yard.

He was also a friend on Facebook, where he once wished her a happy birthday, but they've never spoken in person.

"I feel bad for the girl," said Duncan, referring to a woman found on November 3 chained by her ankle and neck and screaming for help in a shipping container on Kohlhepp's 100-acre farm near Woodruff in northwest South Carolina. "When I first saw [the news], I was like 'wow, what has she been through?'"

The woman, Kala Brown, 30, and her boyfriend, Charles Carver, 32, had been missing since August.

On November 5, Kohlhepp led authorities to Carver's body on the farm. Brown told investigators she watched Kohlhepp shoot her boyfriend, a solicitor said in court.

This week, authorities identified two more bodies unearthed on the property as Meagan Leigh McCraw Coxie, 25, and her husband, Johnny Joe Coxie, 29, both of Spartanburg. The two, who authorities said were known for panhandling beside Interstate 26, were reported missing in December.

It's unclear what led the Coxies to Kohlhepp's property.

'Could have literally been anybody'

"It could have literally been anybody," said Nancy Rice, 23, a massage therapy student living in Clemson, 68 miles southwest of Spartanburg. "It's a very real and scary thing, especially for big cities like Spartanburg and Greenville, and even Clemson, where we have college students walking around."

At least one resident was more surprised that the bodies weren't discovered earlier than shocked at the killings.

"What I've found here are very warm and welcoming people since I've been here," said John Kelly, 59, a Michigan native now living in Boiling Springs, a community about 8 miles north of Spartanburg. "And you hear a story like that, you wonder how can that happen, and nobody sees it."

Kelly said he's "been around the block; it's hard to shock me anymore."

Kohlhepp, a registered sex offender, spent 15 years in jail for a 1987 kidnapping conviction in Arizona.

Last week, police said, he also confessed to a 2003 quadruple homicide that took place at a motorcycle shop in Chesnee, about 15 miles north of Spartanburg.

Business owner Scott Ponder, along with his mother Beverly Guy, employee Chris Sherbert and service manager Brian Lucas were found fatally shot inside Superbike Motorsports on November 6 of that year. Kohlhepp told detectives details that only the killer would have known, authorities have said. He is charged with four counts of murder in those killings.

An attorney for the South Carolina Commission on Indigent Defense, which said it is representing Kohlhepp, has declined to comment on the case.

Worked in a restaurant before turning to real estate

In 2005, two years after killing the four in Chesnee, Kohlhepp met Blackwell at a now-closed Spartanburg restaurant. He worked as a waiter and cook and trained her as a waitress, Blackwell recalled.

He had a big personality and was "really touchy feely," she said.

They became friends on Facebook, but nothing more, she said.

He applied to take his real estate exam in South Carolina in 2006, saying that the Arizona case was his only conviction and he had since followed the law and given back to his community.

Years later, he and Blackwell crossed paths again professionally when the Greenville real estate law firm she worked for handled several of Kohlhepp's real estate closings in Greenville.

Kohlhepp had by then opened his own real estate company, TKA Real Estate, that listed homes in the Saprtanburg area ranging in price from $135,000 to $435,000.

She had ignored most of the messages on Facebook that she said came from his account, including one that read: "tell your man to step off...realtors coming through."

Another referenced "going to my land to move rocks."

The last message from his account was the one from March, and she never responded.

"I got a different job and I knew I didn't have to talk to this guy anymore," she said.

You don't want a guy like that for a neighbor

Kelly, the Michigan native, who is a supervisor at an automobile parts factory, said he had considered buying a home in the area where Kohlhepp lives. He's now glad he chose Boiling Springs instead, he said.

"You don't want to be associated with a man who is now looking like he's a serial killer," Kelly said. "Let's face it, you don't want a guy like that for a neighbor."

The Owenses saw a mention online of Kohlhepp's sex-offender status as they closed on one home in July. They would have tried to get out of the contract had they known the details, Daren Owens said.

He feels relief his family is safe, but also harbors guilt about exposing his family to potential danger.

"I'm reading about how dangerous he was and the kinds of things that he did, I wouldn't want to think, in some way, I put my family or my wife in danger," he said. "That would be horrible."

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