A few questions about visa on arrival in Cairo, for when my wife and I arrive there next week:

1. Is the process as simple as just getting on line at a bank and buying the stamp at $25 per person? And should we simply go to whichever bank has the shortest line?
2. Are there certain bank lines that are for money changing as opposed to visa stamps?
3. We're actually going to be in and out of Egypt twice in a period of about three days. Am I correct in assuming that we need to go through the visa on arrival process twice?

Thanks for any help!