[arockwell]

If you are currently at roughly 0 active users, I would not worry about how much 500k active users cost.

That said, I think something about your cost estimate is way off. It should not cost $75k/mo to host 500k active users. My guess is that either:

  1) Your use case analysis is on the high side
  2) You are using parse incorrectly 
  3) Parse is a bad fit for your application

You can rent 100s of servers from aws for $75k/mo. That should be way overkill to handle 500k active users.