Hi there,
I'm not a REVA, but I just wanted to jump in and say, first of all, welcome to the forums!
Second, the amount of money you make is up to you. It's directly related to how much you charge per hour, how many hours you want to work each week, and how hard you're working to get clients who will pay you what you deserve.
If you want more detail about becoming a REVA, I would highly recommend checking out
The First Real Estate Virtual Assistant Handbook by Kim Hughes. There's a link off on the right side of this page. It has tons of useful info specific to working as a REVA. Be watching for a full review of the book within the next week.
Best of luck to you!