@tytoon
I believe VSC has a few different fax numbers. I don't think they will consider any evidence you send unless they request for it. If you were denied, try going to the field office and explaining your situation. The field Officers have more authority and if they put in an expedite request, VSC is likely to take it more seriously.
@nchetan
My letter was very straight to the point,
1) I explained that I was living off the income from my current position(full time CPT) along with pay stubs for proof
2) I showed them evidence of loans taken out by me and that I needed to pay them back.
3) I also pointed out that my health insurance needed to be renewed, and showed them a termination reminder email from my insurance provider.
4) Expenses for Rent + Utilities/Groceries etc. Did not sent them any bills but gave them a rough estimate of how much I spend in a month.
5) My bank statements.
Thats about it, I told them I wouldn't be able to afford my bills here unless I was approved to continue working at my current position.
The visit to field office helped me lot. The officer there heard what I had to say and did what he could to help me. I believe the officers will not put in an expedite request unless they are convinced by your situation, Whereas a customer service rep would take your info and put in a request right away. I guess this is part of the reason why Service centers take requests from field officers more seriously.
Hope this helps and Good Luck on your Applications!!