The staffing is sorely inadequate at dollar and thrifty car rental in Denver. It is going to take up to three hours to pick up a PRE-PAID car. There are tons of people and three windows open! I'm traveling with my 84 year-old mother and this is just completely unacceptable! If these companies can't provide a reasonable experience, they should reduce their rentals until they can correct this mess! How about adding some kiosks?