HALLANDALE BEACH, Fla. – Family, friends, colleagues and neighbors are mourning a South Florida woman who was killed while vacationing in Costa Rica to celebrate her birthday.
"She was a very nice neighbor -- really big smile, friendly girl," neighbor Joseph Rivelli said.
Rivelli lives two units away from Carla Stefaniak's apartment in Hallandale Beach and remembers seeing her on the day she left for Costa Rica.
"When she was leaving, I happened to be outside and see her with her luggage and stuff," Rivelli said. "She did say she was so excited and happy and (had a) big smile. But yeah, she did say she was going to Costa Rica, and, it's quite sad."
Little did he know that would be the last time he would ever see his neighbor.
Stefaniak's family confirmed overnight that her body was the one found Monday in a mountainous area behind the Airbnb she was staying at.
Her body was found half-buried and covered with plastic bags.
Photos provided by Costa Rican authorities show officers arresting Bismark Espinosa Martinez, 32, a security guard who reportedly lived in the apartment right next to where Stefaniak, 36, was staying.
He was taken into custody after officials said he provided inconsistent statements that did not match up with surveillance video.
"Someone was interviewed and said she left for the airport at 5 a.m. when the flight was much later," South Florida private investigator Wayne Black said. "There was something fishy about that to begin with."
Director Walter Espinosa, of the Judicial Investigation Department of Costa Rica, spoke to reporters Wednesday at a press conference, where he said preliminary information shows that the motive was sexual in nature.
"We went to the villa. This guy shook our hands, looked us in the eye and told us his fake story," Stefaniak's brother, Carlos Caicedo, said. "I can't believe it."
An autopsy showed Stefaniak died from blunt force trauma to the head and had several stab wounds around her neck.
"It's so sad that it had to be my sister in this situation, and she just went there to have a good time," Caicedo said.
Stefaniak's friends and family are left wondering why anyone would want to harm her.
"I'm really sorry for her family and it's just a really sad thing," Rivelli said. "She was really a nice girl."
On the Facebook page "Finding Carla," which has posted updates on the case, Stefaniak was described as "selfless, funny, charismatic, an amazing friend, an avid animal lover and a fighter."
Local 10 News reporter Trent Kelly spoke to Stefaniak's co-workers Tuesday at the insurance office in Dania Beach where she works.
Stefaniak's co-workers said she was an excellent employee who could get along with anyone.
An Airbnb representative said the company is cooperating with local authorities in Costa Rica. The U.S. Embassy in Costa Rica and the FBI are also assisting with the case, Stefaniak's family said.
The owners of the building that housed the Airbnb said they have temporarily closed the facility.