Hi, all:
I have a question which related to divorce and I-751 waiver.
In my case, since the name check takes such a long time as everyone knows, I got my conditional greencard 2 years after the first interview.
right now our marriage goes nowhere, both of us decide to end it.
My question is: my conditional green card only approved one month ago even though our marriage has already last more than two years, and we dated for six years, but I don't keep any receipts for the flowers, dinners..., who knows I need them later

I heard the chances to get I-751 waiver for good faith is 0% if less than 3 months, I am not sure the 3 months indicates which period, marriage or conditional residency?
another question: if we decide to divorce, who should file it first, me or him. shall we seperate first, is it required by NYC law??
third question: since we did not expect this happening, we didn't collect much evidence for this purpose, we just start to work on this after we read the instructions on my conditional residency card. is it required to get all evidences from the begining of our marriage?
forth question: Can my husband write a affidavid letter to prove that our marriage was based on good-faith? Is it necessary? or it is totally ridiculous?
Thanks in advance.