COMPLETE ROBBERY!!!, at Lisbon airport prepaid my 3 week rental for €500. Arrived 1 day late and was told the rental agreement was no longer valid?! Lunacy, how can a car that I paid for already, not be available? I had to re-rent at the counter for DOUBLE the amount! €1000 for the exact same car I had rented for €500, which of course they available, amazing coincidence. After contacting Sixt, they refunded the €500of the initial rental, they should have refunded the €1000. TOTAL SCAM!!! Taking advantage of travellers, like this, shame on you.