In regards to your question about possible ways to finance. In your profile it shows you are from Moldova originally. Are you US citizen/permanent resident? If yes - Stafford loans to begin with. If not, I know there are some partial scholarships may be available at GWSB for Eastern European nationals. Of course there is formal application process and competition, but at least some chance. Try to find out on GWSB site or from whoever you got your admission letter.
Whichever way you do, keep in mind that Financial Assistance Office at GWU is notoriously slow and irresponsive. You will have to take a lead in communicating with them. If you make some mistakes in the process of your application for FAFSA, for example, they will state what is missing or not meeting their requirements, but you will have to fight your way through to find out how to remedy the situation to their satisfaction. It's from my personal experience. Eventually I got what I needed from them, but it was after a lot of broken communication and later then it was supposed to be.
I have some information about my experience at GWSB as a part-time student, so you can get some glimpses:
https://parttimembadegree.com. It's' not exactly the same as full-time experience, but it's still the same Business School, and still same MBA, so you might find something helpful for your situation. Congratulations on your admission!