Hi guys, my conditional green card expires on 01/22/2021. I married an American citizen a few years ago and we're still married. I have a few questions. Please help out if you can. And don't feel obliged to answer all of them. Any responses are much appreciated! Thank you!

1. The earliest date we need to joint file i-751 is 10/22/2020, correct?
2. Besides joint-filing i-751, are there other forms/documents are required to file together?
3. Besides required documents to file, what other supporting documents would you recommend us to file in your experiences? Our joint bank account statement? W2? Tax returns? etc?
4. The total filing fee is $680. One check of $595 for i-751 and another check of $85 for a biometric fee, correct?
5. I learned that the interview could be waived by USCIS and that's certainly up to them. But in your experiences, what chances do you think they'd let you skip the interview? If you didn't have to do the interview, what documents did you file?
6. How long does it take usually for them to issue you the permanent green card? When it's pending, will they issue you something temporary so that you can continue living and working in the US?
7. Any other tips/suggestions you have?