Tech’s “sharing economy” movement has spawned companies like Airbnb and Relay Rides, which let people save and make money via exchanges for things like spare bedrooms and car trips.

Now a new slew of startups is using the model to match consumers with professional services for less.

YourMechanic, for instance, has a mobile network of certified auto mechanics who will come to your home or office; Pathjoy promises “maid service for the masses,” booked online. Similar exchanges are popping up for chefs (Kitchit) and barbers (GoHaircut).

Backers say the new breed of mobile services isn’t just more convenient and cheaper for users; it’s also a way for craftspeople to find steady employment in an uneven economy.

“Most stylists are looking for part-time work to supplement their income,” said GoHaircut CEO Tom Maxim, who hit on the idea while at a New York startup that was trying to take on Skype. Locked into long hours at his desk, Maxim asked if his barber would make house calls; soon Maxim’s co-workers were doing the same, and he moved to Silicon Valley to turn his idea into a company.

San Jose, Calif.-based GoHaircut, launched in October, contracts with half a dozen stylists who will drive to a customer’s home or office, lay down a mat and start snipping.

“The convenience factor goes without saying,” said Sahil Jain, who recently began using GoHaircut for himself and his three employees at San Francisco advertising startup AdStage.

“And $30 per head for haircuts that typically can be upward of $100 just can’t be beat.”

As with most of its peers in other come-to-you markets, GoHaircut lets customers pay directly on its website, so no money changes hands once the professional shows up.

Abhas “Art” Agrawal, CEO of Mountain View, Calif.-based YourMechanic, first began experimenting with online labor marketplaces five years ago, when he launched a site to help hospitals find temporary nurses. When that flopped amid the 2008 recession, Agrawal decided to open a car repair shop.

But while interviewing mechanics, he learned that many of them offered mobile repair through outlets like Craigslist — and realized he could combine two business models into one.

“The problem is, you don’t know who these guys on Craigslist are,” he said. “You don’t know how much it should cost. The whole experience felt broken.”

YourMechanic, which made its debut in September, has compiled a database of automobile part and labor prices. So if the owner of a 2000 Honda Civic needs brake pads, the app can calculate what the job would cost, taking into account how far the mechanic needs to drive, then ship the parts from a wholesaler.

Agrawal said his company — whose investors include actor Ashton Kutcher and venture capital firms SoftTech and Andreessen Horowitz — works with about a dozen certified mechanics who cover roughly half the San Francisco Bay Area.

On-site services aren’t new to the valley; during the dot-com bubble, many companies began offering workers mobile perks like personal training and dentist visits, the better to keep them corralled on campus. GoHaircut, for instance, has a local competitor called On-site Haircuts, which operates a salon inside an RV.

But the company, which was founded in 2003, sets up at specific locations on specific days. “They don’t come to your office on demand,” Maxim notes.

The new wave of such services is built, in part, on the increasing ubiquity of mobile phones, which make it easy for customers to schedule services on the fly and for workers in the field to be notified of new clients.