A week after the listing was posted in March 2022, Mr. Jalali, now 21, said, “A couple walked in like, ‘We’re here for the steak.’” The roommates turned them away, but their listed phone number rang off the hook. The friends toyed with the idea of opening a real restaurant, and Mr. Walz, also 21, built a website with a waiting list.

This sounds like something I would’ve done in my mid-twenties.

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