A few things, You will find more expert and knowledgeable answers on A Candle For Love,
http://candleforlove.comExample from their extensive FAQ section:
QUOTE
Q. 1.3 What are the requirements to directly file at the consulate?
A.1.3.1
As a general rule, the petitioner must reside in the consular district but the residence or even physical presence of the beneficiary is immaterial. The petitioner must execute the petition in person before the consular officer.
A.1.3.2
You do not need to wait 6 months after you get your residence book. I only had my residence book for a few weeks before I filed. And I know people who filed the day after they got their residence book.
A.1.3.3
I am only familiar with DCF and the process has taken roughly 7-8 months to get to the interview. I am already married and we filed the I-130. See, we weren't any different once we sent the P3 back, before that, you save a lot of time by avoiding the American centers. If one is truly determined, get married in China, live there for two years and then come America.
A.1.3.4
The employer takes care of obtaining a work permit (z-visa) and a residence book. Usually takes 2-3 weeks including a medical examination. As soon as you get a residence book, you can file DCF and immediately leave China if you want (although you might face penalties if you are tied into a contract).
A.1.3.5
I believe the big requirement is the residency permit. I don't think they care about the kind of visa. They did want to see a Z visa when we filed, but when I showed them the permit (I think I was on an X visa), they didn't seem to care about the visa…
http://cflgallery.com/FAQ/CFL_FAQ_DCF_Final1.htm#Q1_3http://candleforlove.com/forums/index.php?showtopic=19303David on CFL is THE EXPERT about all things regarding how the consulates in China work.
A notarial Birth Cert is obtained at the Notarial office that has jurisdiction over where your SO lives, the Notorial office can also translate the certificate to English, and bind the translation in the book, they can also do this with other things like marriage certificate, and police certificate.
I highly recomend that you join CFL, and use their resources, no site is better for asking questions, and preparing for immigration from China.