We arrived at 1325 having booked the car from midday and were told that it was no longer available as it had been rented out to somebody else. No like for like replacement, instead got a much bigger car that wasn’t what we needed or wanted. We were told there was no alternative. At no time were we told to pick up the car at the exact time for which it was booked. Otherwise a reasonable experience.
We booked the car the day prior and the short story is, construction has caused the office to relocate. It wasn’t clear to where they had relocated and there were a couple of signs posted that read “Sixt” with an arrow but no specific direction. I walked around for almost an hour looking for the place. There was another Sixt office in the downtown area but they were closed. It was very frustrating and I ended up finding a car with another agency nearby. I sent Sixt a note and their response was pathetic. They provided me with the address. The address that is inaccessible because of construction. Ridiculous.
Get the insurance. The negative reviews are accuate in that they do not take any time at pickup or dropoff to inspect the car, and just tell you that they will "email you an invoice for any damage". But they are very very clear when you go to pick the car up that if you refuse their insurance you will be charged for every single scratch, chip, dent or crack. Since they don't actually inspect the car with you, you are likely going to pay for any small detail on the car. So even if you have third party insurance, just avoid the hassle and pay the insurance (online ahead of time - it's cheper) and you can get in and out of the lot quickly. Which, as reported, is hard to find. The rental kiosk is on the train platform, then you have to walk down the street about 10 minutes to the lot - which is very hard to find when you return, and Google maps won't help.
Hidden fees and cumbersome process
Great experience renting. Everything was as expected and staff were friendly and prompt.
Ljubljana office said there was a Dropbox in Prague. THERE IS NOT. But we spent an hour—at midnight—looking for it. We will see if a discount is forthcoming.