Rented a car from Dollar Denver Airport. As we were ready to return for our flight, we noticed a flat tire. There was no spare or fix a flat. We tried pumping it up but it would not hold air. Their roadside assistance was of little help. We had to catch a ride to the airport, stopping at Dollar on the way. They got the keys and towed the car in the next day. Now they are charging us a $39 fee because the car was late as well as $168 for the tow. They left us stranded with an under equipped rental and are charging us for it. No one with Dollar could tell us how else we could have handled it. Their bottom line was "sucks to be you". Never.....ever.....rent from Dollar!