Tommy27

When I went (In August 2017), I brought everything you mentioned plus a copy of all the forms I handed in. Plus pictures and proof of bona fide marriage. I put it all in a nice little picture book, I'm a guy and it's the first time I did scrap booking. But your list seems good. This is the interview, just exhaust all your copied info and bring it all. If they dont ask for it, thats fine. But at least have it just incase. Your list does seem fine tho . They only took our Medical exam, because mine was out of date.
 
Our interviewer was amazingly nice, mabe we got lucky there. He took our Medical Exam and I think that was it. He asked to look at pictures so I showed him awkwardly (We aren't really picture people). Other than that we chatted, Me and my spouse are Gamers and he was one too. So we had a nice little chat about the latest playstation games and VR. It was surreal to be honest. I talked to my USCIS officer about video games? *Facepalm*
 
But ofc it was for him to see us interact, etc... thats the most important think I think for the interview. Just a little side story for you hehe.
 
But yeah, we had all our documents. He only wanted pictures and our Medical exam. But I think always bring everything, copies of your whole application. Evidence , the works. Just incase.

Renew it.   Technically, an expired passport shouldn't be a problem, but I'm assuming you probably want to travel at some point, so getting it renewed is probably for the best. Also, an expired passport may not be accepted for all purposes as a form of acceptable photo ID, and having a valid photo ID (i.e. a driver's license) is generally encouraged.

Not really. Have your proof of a bona fide relationship ready, including co-mingling of fiances and such. You'll likely need a new medical as well. All that will come later, though.

Nope. Your case sounds pretty straightforward and DIY. All an attorney can really do for you is (if they're decent) remind you of the forms to send and act as a second set of eyes. They can't speed it up and aren't likely to increase your chances of success for a simple case.