Hi,
I started dating my fiancée via Internet almost two years ago. About nine months after we started dating, we spent a couple of weeks together in a country we were both visiting. Afterwards, she filed for a B-2 tourist visa. Her application was accepted and she visited me for three weeks this summer. During her stay, we got engaged. In a few weeks, I will visit her and her family in her country for a couple of weeks. Afterwards, I intend to submit the I-129F so she can file for a K-1 fiancée visa. Before we submit the forms, I just have a few questions that I wanted to clear up.
(1) We haven't gone to an actual immigration lawyer for advice. We're not broke, but we are both students and are trying to be frugal. The process for applying for a K-1 seems fairly straight-forward, so we were attempting to do it by ourselves. Is it really as easy as assembling all the supporting materials and submitting the applications, or should we go to a lawyer to help us with the process?
(2) I'm currently employed by my university as a graduate research assistant. I have a salary of ~$20,000 and will have that salary when we file the applications. However, I will be graduating before she is able to come for the wedding. I will have a another job by that time (with a much better salary), but it's obvious that I won't have my current salary at that time. Will that be a problem? If so, I shouldn't have a problem getting a cosponsor. Also, would it be advisable (or help in any way) to get a cosponsor even if it wasn't a problem?
(3) As I said, my fiancée currently has a B-2 visa. Will she be able to visit me here in the United States after we file for the K-1 but before the application is approved/rejected? I know that she can be rejected based on an intent to immigrate, but is that avoided due to the K-1 technically being a nonimmigrant visa?
Thanks for the help!

