In the past, each team was given tickets so it was “free.” I don’t know if you are allowed to buy tickets on top of that, but I don’t think so. It was packed with teams.
Last time I went to Finale, (read: 2013) you could buy tickets at one of the front booths. I don’t remember exactly how much it was, but it was in the neighborhood of $35ish or so if you didn’t buy a package deal when your team registered or went sans team.
It used to cost 35 per person if you did not use the FRC housing system.
The last few years all you have to do to go to the Finale was to have wrist bands. These are given in your registration packet when you sign in at the competition.
You will have to log into the experient event website and register all the team members prior to arrival. I have heard they added an external kiosk to generate badging for after the fact.
All of the official FIRST events you listed above are free and open to the public with name badge/registration (which is free). The finale is also free and open to anyone with a name badge.
Someone mentioned before that the parking ranges in price and is pretty standard. There are many lots close by that are $5-10 for the day, and there is a parking garage right next to the dome.
We went to CMP in StL last year, and didn’t pay any parking fees, and did not have to show a badge until we entered the dome/convention center. I usually went in a team mom’s car rather than our bus, and we never paid for parking, nor had a special “parking pass”, and parked sometimes on the street, sometimes in the near-dome lots. My understanding of the admin rules is that all FIRST events are free admission to the public.