Samantha's boyfriend spoke to the mourners before breaking down in tears while sitting in the front row.
"I was on the phone tracking her to make sure she got home safely and immediately knew there was something that was wrong," the boyfriend told the group. "Unfortunately, I was two and a half hours away. I would do anything to go back."
Authorities said the University of South Carolina senior was last seen getting into a car that she thought was her Uber.
The suspect, Nathaniel Rowland, was no Uber driver.
Charleston police said he had activated the child safety lock after Samantha got into the car preventing her from escaping.
Her body was discovered a day after she disappeared. Police said she died from multiple sharp injuries.
"He was a monster, right?" said Samantha's father Seymour Josephson. "I don't want anyone else to go through what I did as a parent."
Seymour is now calling for action that Uber and Lyft drivers do more to identify themselves.
One by one, Samantha's high school friends and neighbors shared their favorite stories that they called "Sammyisms."
"As soon as they started telling their stories, you played a story in your head, just her infectious giggle. She did light up a room," said family friend Kim Levy.
"(She) was just happy, it's all you could say about Sammy," added Beth Logue, whose daughter was friends with the 21-year-old.
Bound for law school at Drexel University, her parents said she came home two weeks ago to celebrate Student Acceptance Day.
Samantha Josephson's funeral is scheduled for Wednesday in Princeton Junction, New Jersey.