Mystery shopping lets you get a complete car service without paying a penny—as long as your vehicle isn't too old. A smart strategy I've used successfully.
I've shared before how mystery shopping can earn you extra cash through visits to clothing stores, restaurants, or phone providers. But here's how I applied the same principle to get my car's full overhaul done for free.

After registering on reputable mystery shopping platforms like Qualimétrie and Qualisens, one reached out with an opportunity for a garage visit to service my car. The overhaul was fully covered up to €300—covering the entire bill.
From booking the appointment and drop-off to the final review, everything is evaluated in detail. You'll complete a questionnaire covering reception, workmanship quality, and speed. It takes about 30 minutes, but with all service costs covered (excluding any extra repairs), it's well worth it.
For a €280 service, I paid nothing out of pocket, plus I earned €15 for the visit and €4 in mileage reimbursement.
The only drawback: These opportunities are typically for cars less than 10 years old. I used my parents' newer Scenic since my own car exceeded that limit.
Similar visits are available for oil changes, often covered up to €95.
What do you think about getting your car serviced for free this way? Would you give it a try? Share your thoughts in the comments.