Shaun,
When I did my K-1 last year, it took us about 6 months from the time I sent the package in and to the time we had our interview at the GZ Consulate. I did everything myself and did not hire a lawyer (sounds like what you are doing). When I did my wife's (fiancee at the time) work history, I just put the name and addresses. Just make sure there is not any major gaps in the times. I just put month and year for one and then continued from that date. As far as the letter of intent to marry, I just had my wife write an e-mail in english and send it to me. Her email address was the proof that she sent it to me. It does not have to be notorized. You could always explain that your financee had a friend who speaks and writes English helped her write it. I then just wrote out my letter and printed it out. I went to the interview with my wife. That make it look better and shows that you are really going through with it and are not bringing her to the US for some other reason than marry her. My wife did not speak much English and was worried. When the person interviewing her asked if she spoke English, she said, "Gucci, Prada, Louis Vuitton". He laughed. He spoke a little chinese and had translators available. I think it would be rediculous if they expect your lady to speak fluent English. They know many do not speak much English. After the interview, we waited a few days before picking up the visa at a nearby post office. They do not give you the visa on the same day, so plan on sticking around or coming back (meaning stay at a hotel). My wife is from Chengdu and we were not going to fly back to Chengdu and then fly back to GZ. Good luck and let us know if you have any more questions or what to expect later.