Based on the entire experience both during and after rental, nothing at all to like.
DO NOT TRUST THEIR STAFF OR VEHICLES OR CUSTOMER SERVICE AFTERWARDS!!!!! Upon check-in, I was advised the SUV I booked was not suitable for Tahoe winter (shouldn't all SUVs be winter-ready?!) so forced to pay double original booked total for a different SUV. That vehicle was NOT equipped for Tahoe winter - faulty frozen wiper fluid, bad windshield wipers, engine light on, brake noise on day 1,2! Wasted Hours on multiple days on addressing vehicle faults, and yet was not given even 1 hour extra to return the car on final day. I have spent 8 MONTHS trying to get reimbursed for the upsell charges I paid despite being given a vehicle that could not perform any better than original SUV booked at significantly lower rate. DO NOT RENT HERE because if there are issues you will not find ANY way to contact SIXT to get issues addressed. Every option by phone or website leads to literally no person or error messages on their website. Only when I finally gave them bad review on Yelp, months later, did someone reach out to me and tell me to email them and even then I had to follow up 2 times to get a response. STILL NO RESOLUTION after 8 months. I think they want you to eventually give up so they can keep your $. WORST EXPERIENCE EVER.