If you want to open a restaurant, you sure as hell better know how to screen for qualified waiters/bartenders.

Sure, but you'd better be able to tell if the servers you hire are doing a good job. Ditto for cooks, cleaners, dishwashers. You shouldn't need to hire someone to look for flecks of food on your 'clean' dishes.

Alternatively, if you want to open a restaurant, you shouldn't need to be an expert in plumbing, electrical, framing, HVAC, upholstery, cabinet-making, painting, and floor refinishing just to get the place ready to open.

The reason you don't need to be an expert in all these things is because there are governmentally mandated codes, licensures and bonds with which all such workers must comply or face governmental censure. These standards have supposedly been crafted to represent an acceptable minimum quality of work by qualified persons.

Sure, but you hire professionals to perform and inspect this work, and at the end, have a local official verify the work has been done. Your example really stretches the analogy as buying/renting a structure is not at all similar to trying to get a stranger to build a core product that you can't maintain.

That might be a better analogy, yes.