No it is not a legit job. There are many outfits out there that will sell you lists of companies. You can get those lists for free on this forum and others. There are companies that will send you 'referrals' for shops. You can find those jobs usually for free at Jobslinger.com. When any company is asking you for money to shop, just move away. I have never paid to shop and have no intention of ever doing so. It just is not necessary. Mystery Shopping companies most frequently post their available jobs on their websites. Sign up with the company as a shopper and you can see what is available for yourself.
Note: The ads at the top of this page are automatically generated by Google Ads by folks willing to pay Google to advertise. The owner of this forum has chosen to have the ads on his forum to help defray the costs he associates with the forum because Goggle pays for the privilege of putting ads on a web page.