LIVONIA, Mich. — A few months after Dayna Freeland bought her 2008 Ford F-150 last year, she discovered the frame was so badly rusted that it was in danger of breaking apart. Rather than storm into the used-car dealership to complain, though, she took the truck to My Mechanics Place along with an uncorroded frame she had picked up for $200 at a salvage yard.

A week later, Ms. Freeland, a 22-year-old doctoral candidate in physics from Milford, Mich., who is also an actor and a model, drove away in her newly stable truck, with a rebuilt timing system to boot. Her total cost was a little over $2,000 because, despite having never done such a thing before, she did all the work herself.

My Mechanics Place, in suburban Detroit, is among a couple of dozen do-it-yourself auto repair shops in the United States. It provided the bay, the lift and some tools for $125 a day.

For the rest, Ms. Freeland read parts manuals, watched YouTube videos and chatted up the more experienced D.I.Y.-ers working at the garage.