Using real places

As long as you don't say anything negative about the institutions that you can't prove to be true, you should be fine. If your character has any negative traits, you may want to ensure you don't describe him in a way that ties him to any individual real person (e.g. there's only one person who does the job you describe) also.

It's okay to use the name of real places, so long as what you write isn't damaging. If it is, that may mean a lawsuit.

But having real places used neutrally (or even favorably, as with the people meeting in a good restaurant), is fine.

Don't worry too much -- when your book is purchased, the publisher/editor will have everything vetted, and will ask for changes if they think the description is a problem.

I like to make them funny.

When I'm writing for fun (usually), I like to fictionalize the names of real places. I like to make them funny. Like the Biltmore Hotel might become the Bilked-me Hotel or the Grand Hyatt will be the Brand Buy It Hotel.

I've also left out names but given details of the place and a description like "her favorite downtown bistro" or "the Adam's Morgan shoe store they frequented on weekends" and probably went on to give the location without giving an address.