It's 11 p.m. on a Saturday, and a group of 20-somethings are getting picked up by their Lyft driver, Vanessa Nelson. They have no idea what's coming to them.
As they climb into her van, she switches on flashing pink lights that illuminate a disco ball.
"Oh, wow. This is legit!" exclaims Jefferson Santos.
"It's a little party in here!" says Jessica Montoya.
Nelson greets them, saying, "So this is Karaoke Mood Lyft, where you get to be a star."
The stage is already set. Nelson has tricked out her Chrysler Town & Country minivan with extra speakers, wireless microphones and a laptop that does karaoke. After her passengers finish taking selfies with the disco ball, they pick a song: R. Kelly's "Ignition."
For the entire ride from National City to a club in the Gaslamp Quarter, they sing.
Nelson has been driving for Lyft since it started in San Diego last summer. The rideshare service allows regular people to act as taxi drivers, transporting strangers to their destinations for a price. Drivers mark their cars with fuzzy pink mustaches and use an app to arrange passenger pickups. In San Diego, rides cost $1.75 a mile and 25 cents a minute, plus a $2.50 fee.
Although other cities' transportation departments have tried to ban Lyft and other rideshare companies because drivers don't have taxi licenses, Lyft has so far been uncontested here.
Some drivers give their cars a theme to treat passengers to a ride that's above and beyond what they'd get in a normal taxi. Nelson is one of them. She has kicked up her Lyft rides to a new level, turning her van into a karaoke party where passengers sing as they ride.
Nelson hadn't heard of Lyft a year ago, and thanks her 11-year-old son for getting her a driving job.
"I guess my son kind of overheard that I needed work," she said. "He went on my computer and saw an ad asking for Lyft drivers on Facebook. I think he did me a big favor, a huge favor, and went and filled out the application."
Lyft called her a week later, and after two interviews and a car inspection, Nelson became one of the first Lyft drivers in San Diego. Paige Thelen, a company spokeswoman, said she doesn't know exactly how many Lyft drivers operate in San Diego, but estimates there are hundreds. Drivers set their own hours and generally get 80 percent of passenger fees.
In Nelson's next stop of the night, she picks up Andi Christensen from a bar tending job downtown. Christensen is by herself, completely sober and is just heading home, but she still wants to sing. She doesn't hesitate for a second when choosing her karaoke song, "Paul Revere" by Beastie Boys.
Unfortunately, not everyone can rap like Christensen. Nelson next picks up a young guy from a bar in Pacific Beach. Although he says he hates singing, for some reason he agreed to sing Journey's "Don't Stop Believin,'" followed by two Eminem songs. Halfway through each rap, the young man, who understandably wouldn't give his name, realized he couldn't keep up.
Just before midnight, Nelson pulls into a parking lot in Pacific Beach to look up an address on her phone. Her van is immediately mobbed by five or six people who are drawn like moths to her flashing lights.
"Is this Cash Cab?" one woman asks, her eyes wide.
"No, this is Karaoke Mood Lyft," Nelson kindly explains before telling the partiers to download the Lyft app on their phones so next time they can request a ride. She doesn't mention that because Lyft sends the nearest driver when you request a ride, getting Nelson's karaoke car is pure luck.
Nelson said 80 percent of the passengers she picks up are drunk, even on weeknights.
"It doesn't matter to me if they're drunk. I'm just thinking, 'Gosh, they're having so much fun,'" she said.
As if on cue, Kimberly Topuzes then climbs into her car and requests Lady Gaga. Topuzes had been at a bar with friends but is headed home by herself at the early hour of about 12:30 a.m.
As she finishes singing "Just Dance," complete with hand motions, Topuzes shrieks, "I know I'm not the best singer, but that was awesome!"
There are a lot of electronics and screens plugged into Nelson's van, but she said she isn't distracted by them when she's driving and hasn't had trouble with police.
"I've been through DUI checkpoints, and usually they just let me pass," she said. "Sometimes they check to see what's going on inside, and they're like, 'Hey, is there a party going on in here?' And my response is, 'Always officer, always.'"
Nelson drives for Lyft seven days a week, from after dinner until 3 a.m.
"It's actually my social life," she said. "I love my kids, I love my home, but it takes me to where I get to meet people, and socialize and have fun."
Nelson has seven kids, four under the age of 11. Their dad watches them while she drives, but she wakes up with them most mornings.
"Sometimes I come home and I sleep two hours, and then I take naps," she said. "Sometimes the kids will be quiet, and then I get to sleep a little more."
Nelson makes about $700 a week from Lyfting, which supplements her kids' dad's salary and money she makes from Plant Lover's Delight, a side landscape business. But the Lyft money definitely helps out her family, as does her karaoke car.
"My kids love singing in the car," she said. "We're just parked there in the driveway with the engine on. One of their favorite songs is 'What Does the Fox Say?'"
Nelson's go-to karaoke song is Whitney Houston's "The Greatest Love of All," because it makes her think of her kids.
It's close to 2 a.m., and Nelson hasn't even stopped for a bathroom break since she started driving seven hours ago. But she seems to genuinely be having fun as she sings solo along with her karaoke machine.
Then she waits for other passengers to request a ride, and a song.