A teenager who has set up a website so people can rent out their driveways or garages to commuters is expanding his business to his native south Wales.
Tom Page, 18, set up youcanpark.com, which matches the spaces with motorists struggling to find parking.
A trial in Bath and Bristol saw 60 residents sign up to let their unused space either five or seven days a week.
Mr Page, originally from Church Village near Pontypridd, said premium spaces in Cardiff could earn up to £250 a month.
Having just finished a business A-level, Mr Page was on a gap year and working in a call centre in central Bristol when he came up with the idea.
"I had to park three miles away and walk into work" he said. "I was walking back one day and saw lots of spare driveways. That was my eureka moment. They were wasted space and I would have loved to have parked on those driveways so close to work."
Residents advertise their space on the site for free, but pay a commission. Users then search for a parking place in their chosen area, apply and, once approved, can rent it.
Mr Page said: "We fully manage it like a letting company does. We collect payment and pay the person who owns the space."
The teenager, whose company is based in Bristol, said he has received 500 email inquiries, has clients in Manchester and London and now employs six members of staff.
"Our biggest challenge has been getting people to realise their unused parking space can earn them money" said Mr Page. "If you've got a flat, you always rent it out. Parking is a massive problem in cities, so a space is prime real estate."
Mr Page, whose Welsh business will initially focus on Cardiff and Newport, said: "Cardiff is getting more popular, the university is getting bigger and parking is a nightmare. We are using wasted space, there will be less cars circling, less congestion and less emissions."
One of his first customers in Cardiff is 29-year-old Francois Bourlier.
A salesman, who does not own a car, he said he hoped the car parking space at his flat in Landmark Place in the city centre would earn him up to £100 per month.
He said: "I just want to get some money for something that I don't use. I don't really want a car."
Mr Bourlier said he helped put down the deposit on his flat with money he made from buying a parking space in his native France for 8,000 euros and selling it two years later for 12,000 euros.
He said: "In France, the car space business is very big, especially for young people. If you don't have a lots of money and you can't buy a house, you buy a parking space in a central location. The increase in equity you can make on a car space is much higher."