This is the stuff we had for our AOS interview. Now, I wasn't really "established" prior to Tamer getting here. I graduated from college 2.5 years ago and still haven't gotten really settled in.
Pictures - My husband loves to take pictures, so we have maybe 20, a few with our friends, some from trips we took to the zool.
Wedding pictures - we didn't have a big wedding, just a 5 minute thing at the mosque. So, we had some candid shots from that. The interviewer was very taken aback that we didn't have a reception and that no family and friends were there. But, we explained our reasoning, and she was "ok" with it after awhile I guess.
Health insurance - He's on my health insurance
Joint Checking/Savings - We have a joint checking/savings account, but will both have our own savings accounts as well, to keep our personal funds in. We set his up when he got here, but I'm too lazy to seperate out my own money at this point.
Apartment - We're both on the lease
Utility - We're both on the electric/cable bills
Car title - my parents gave us a car when we got married (alhamduililah), so both our names are on the title, even though my husband doesn't know how to drive.
Taxes - we filed taxes jointly as well
Letters addressed to both of us - wedding invites from my friends inviting us to their wedding, cards from my family congratulating us on our marriage
Letter from my job - stating that Tamer was listed as my spouse in their files
For our interview, I kinda shoved all our evidence on the lady quickly. I was nervous and just chucking things across the table

She kept all the evidence we had, although I don't know if that's because we threw it at her or because she really wanted it.
We got approved the same day. I don't know if it was beause of the evidence, or how smooth we looked. A lot of the people in the interview room were wearing jeans and tshirts carrying manila folders. We wore business like clothes, carried a briefcase and had everything arranged in a photo album with folders inside to hold the evidence.