I booked a Sixt rental for a trip to NYC. I now avoid Sixt at all costs. My flight to JFK was delayed, and no one answered when I tried to contact Sixt from their website to change my arrival time. As a result, they closed their counter at JFK before I arrived and left me stranded late at night. I ended up booking from Avis (office was still open, thankfully). Although I was unable to contact Sixt, they still charged me for the rental I never used. And they didnt respond to my follow up inquiries. Their customer support was overseas and sounded like a boiler room.