Epic Pass mountains (Vail Resorts) currently have a reservation system which is a pain. When they announced this I thought the mountains would be less busy, but this weekend Keystone was packed so I am not really sure what a reservation system is accomplishing. Parking depends on what mountain you go to, Keystone has some free options that are decent but at a place like Vail the only free option is to park along the frontage road north of I 70 and then ride a bus.