Carla Stefaniak of Hallandale Beach, Florida, went to the Central American country to celebrate her 36th birthday but never boarded her Nov. 28 return flight after messaging friends that it was "pretty sketchy" at her resort. That prompted her family to raise the alarm with Costa Rican authorities.
Officials later found a partially buried body in woods near the Villa le Mas complex and identified it using fingerprints, the country's Judicial Investigation Department said. Stefaniak's family members also traveled to there to help with identification.
Security guard Bismark Espinosa Martinez, 32, was arrested in the slaying after he contradicted himself in statements to police, the department said Wednesday. Investigators said blood was found in his nearby apartment.
"What happened to Carla is just unimaginable," friend Bugra Demirel of Tallahassee said in a telephone interview. He said Carla was a "happy soul" who made everyone laugh and had a large social media presence.
Espinosa Martinez, a Nicaraguan immigrant, was working as a security guard at the complex despite lacking the proper documents to be in Costa Rica, department officials said at a news conference in San Jose. He is believed to have lived in Costa Rica since June.
Airbnb removed Villa le Mas - a compound with seven vacation apartments - from its site and said Wednesday that it had reached out to family members to offer condolences. Villa Le Mas's attorney, Federico Jenkins, said the owners are cooperating with the authorities in the investigation.
Stefaniak, who was an insurance agent, loved to travel and post photos on Instagram. Her trips included visits to Iceland, Switzerland and Mexico, all documented on social media.
For her birthday, she and her sister-in-law decided to visit Costa Rica for a short trip.
As with her other journeys, Stefaniak posted photos on her Instagram. On Nov. 23, she posted a photo of her looking at the ocean that said, "Future resident of Costa Rica." Two days later, her last Instagram picture featured her in a turquoise bathing suit, lying near a pool with tropical plants in the background. "I'm going to miss the place," she wrote.
On Nov. 27 - her birthday - Stefaniak's sister-in-law returned home; the two women had booked different return flights on different days. Stefaniak reserved an Airbnb about 10 miles (16 kilometers) from the airport in San Jose for her final night in the country. Language wasn't an issue; Stefaniak was born in Venezuela, then moved to Tampa in 2000 with her family and finally settled in South Florida.
After her sister-in-law left, an Uber driver took her on a tour of San Jose, then dropped her off at the Airbnb around 5 p.m. on Nov. 27.
Demirel said she texted a friend that it was "raining crazy" and the power was out. She added that it was "pretty sketchy here" and included a picture of the Airbnb.
"Everything she did she always shared with friends and that's when we knew definitely something was up as soon as we lost contact with her," Demirel said.
After Stefaniak failed to board her Nov. 28 flight to Florida, the family discovered a troubling detail: she had checked in for her flight on the 26th. The family alerted Costa Rican authorities and launched a social media campaign to find her.
Then came a break: the hotel guard said he'd last seen Stefaniak at 5 a.m. on Nov. 28 and helped her put her bags into a taxi. But then he changed his story, according to Costa Rican media, and authorities scrutinized the details more. The family wondered why she would have taken a car to the airport at 5 a.m. when her flight was in the afternoon.
On Tuesday, a body was found half-buried and covered in plastic in a wooded area about 1,000 feet (305 meters) from the hotel. It was Stefaniak.
An autopsy revealed that Stefaniak suffered a blunt force wound to the head and cuts on the neck and arms.
On Wednesday, her family worked to bring her body home so they could make funeral arrangements.
"It's too much for us," her father, Carlos Stefaniak, told ABC Action News in Tampa from Costa Rica. He showed a photo of his four children - Carla and her sister, and their two brothers. "That's my team. They are incomplete."
Demirel wondered if the culprit planned to harm Stefaniak from the moment she booked the reservation because her profile photo shows she's "beautiful" and she noted in her reservation that she was traveling alone.
Airbnb encourages users to post their photos as an "important way for hosts and guests to learn about each other."
"I want people to know these things happen," he said. "Girls traveling alone make decisions to stay at places. We want them to be aware of their surroundings. But it is hard to have fun and have your guard up at the same time."
Reporter Javier Cordoba in San Jose, Costa Rica, contributed to this report.
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