If you stay at the 4-Queens the parking in the garage is free. For as long as you are staying at the 4-Queens.. Just be sure when you check in you get a parking pass from the hotel desk clerk. Everytime you leave the garage you will need to show it and sign the parking ticket you got upon entering the garage each time.

As I understand it Helldorado Days is a yearly western/cowboy themed event in Las Vegas. I have never been in Las Vegas for the Helldorado Days. So I donot know exactly what goes on during these Days.
Win a bunch of strikes and have a great trip.
Dan from Louisian