Dave Koester lives in the neighborhood facing Keller Drive, just across the street where Boyer was fatally shot Tuesday. He says there has been a rash of violent home invasions in his community.
"There were some home invasions where they actually injured the owners; they pistol whipped him, things like that," Koester said.
Keller Avenue feeds into Interstate 580. Residents believe the highway has become a convenient route for predators.
One theory is that Boyer may have been the victim of a robbery attempt. He was shot near the stop sign on Keller and Hansom drives about noon Tuesday. The killers were in another car.
"We believe the suspect exited the vehicle, approached our victim and shot inside the vehicle," Oakland Police Sgt. Arturo Bautista said.
Bautista says investigators do have shell casings and they've been sent to a crime lab. The casings images will be entered into a national database to see if there's a match with a cartridge from another crime. If so, police may be able to determine who fired the gun.
Police did find a witness early on, an elderly woman who lives in the area, but Bautista says that witness was of little help.
"The witness out there only provided limited information, didn't really get to see what happened before," he said. "So, that was very limited in terms of what we had."
The witness did tell police she thinks the shooter may have been in a brown car.
Even though police have yet to establish a motive, investigators believe this was not a random act of violence.
"If people are approaching people as they're traveling in their cars or stopping them, we haven't had anything like that so we think this is kind of an isolated event," Bautista said.
ABC7 News has learned in addition to saving lives as a paramedic, Boyer helped make our community better in other ways as well.
Mary Holliday of Big Brothers Big Sisters knew Boyer for three years. She is the one who matched him up with his "little brother" who's now 14.
"It's just sad in general," said Holliday. "That's what he gave me... is that he cared, he truly cared and he wanted to give back his time and now his little brother won't have that."
The Santa Clara County paramedic also volunteered at the Order of Malta free clinic in Oakland and had just been accepted into the physician's assistant program at Stanford. His wife and family have decided to donate his organs. Late Friday, Boyer's wife and family issued a statement which says in part, "Quinn's passing leaves a gash in our hearts that will never heal."
There is a memorial at Boyer's ambulance company in San Jose. Arrangements are being made for his little brother to visit the memorial and to attend the funeral.
"I can only imagine what his little brother is going through right now because they were close," said Holliday.
Crime Stoppers is offering $10,000 for information that leads to the arrest of the shooter.
(Photo of Quinn Boyer courtesy of Angie Perez)