Other than the application form and two passport photos and the check there are no "required" documents. The burden is on you to demonstrate that you have continued to have a good faith marriage. The choice is yours of what to include but good documents are joint tax returns, birth certificates of children born during the marriage, joint lease or mortgage, joint debts, joint credit cards, health insurance, car insurance, car titles, Costco membership, joint cell phone bills. family gym membership, etc. In other words every day stuff showing you are actually living together and commingling your lives.
Lynne R. Feldman, Attorney at Law
Aside from the Form signed and dated by both of you, and, of course the check to DHS, it is really up to you what you want to include as proof of your lives together as s married couple. A very good list of those documents is contained on your I-485 interview notice (remember that one?) Dig it out and review it. The more "stuff" you send, the less the chance you will be scheduled to a second interview. Of course, if you have kids together and send their birth certificates, that in and of itself is worth more than half of all the other stuff you may be expected to attach to the I-751.
Behar Intl. Counsel 619.234.5962 Kindly be advised that the answer above is only general in nature cannot be construed as legal advice, given that not enough facts are known. It is your responsibility to retain a lawyer to analyze the facts specific to your particular situation in order to give you specific advice. Specific answers will require cognizance of all pertinent facts about your case. Any answers offered on Avvo are of a general nature only, and are not meant to create an attorney-client relationship.
The only real challenge to your application would be if the marriage was spurious. Absent that, you should be fine.
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If you want to increase your chances of avoiding an RFE or a second interview (which is possible), hire a good lawyer to do this right the first time around. It's not a specific item that will make or break your application but rather the totality and quality of the items you do submit. Consult a good lawyer to see what's enough in your particular case.
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