One minute after I drove out of the SIXT lot, the "Oil Pressure Low" light came on. By the time I was able to pull over (I was on a highway so I had to wait for an exit), the engine was smoking. I opened the hood and could see oil gleaming on parts of the engine and when I checked the oil, there was none. I happened to pull over outside of an auto parts distributer and when some of the guys working there came over and checked, they confirmed that there was no oil and recommended I not drive back to the airport, since the engine could catch fire. My mother and I ended up waiting for 4 hours in what became a deserted and dark parking lot for the tow truck to show up with a different car for us. By the end, we were worried about our safety (since we were two woman alone in a deserted place that we weren't familiar with). Every time we called for an update on the tow truck, customer service was friendly, but also kept making promises that they didn't keep (like, "we'll call and check back with you in 5 min", then we'd hear from them 45 min later. Or, "it will be 30 min", when it was another 1.5 hour wait). We ended up having to book a $135 hotel room, since we finally got our car at 8:45 PM and still needed to drive 3.5 hours to where our AirBnB was. When I asked for reimbursement when I returned the car, the folks at the counter were very understanding and tried to be helpful, but I was told they didn't have the ability to credit us with that much money. They said the manager would call me the next day. 4 days later and after me calling once to see if I could get ahold of him, I still haven't spoken to that manager and don't want to waste any more of my time on this. I am very frustrated that an error on SIXT's part (giving me a car with no oil in the proper place and oil on the engine) resulted in me having to pay an extra $135, waste 4 hours of my 3 day trip, and cause my mother and I to sit in a deserted parking lot in an unfamiliar area after dark. The new rental delivered to us was an upgrade, which was nice, but I was never given the option to have a new car that was the same level and be reimbursed for the hotel room, which I would have much preferred. I will not be renting from SIXT in the future.