Thrifty Car Rental Misleading Information to Coerce Me Into Upgrading to a Car, and Poor Customer Service San Francisco CA

On September 2, 2023, I arrived at SFO Thrifty Car Counter. First, the wait was very long (~90 minutes) and kept growing. I had reserved an EV, so I asked if the car I will be getting uses a CCS or CHADEMO port, and the agent said he didn't know. This is equivalent to not knowing what octane of gas a car takes. He then says they don't have the Kia Niro, which was the car I was supposed to get, and that they have Chevy Bolts but are running low and ask if I want to upgrade to an SUV at $50 a day. I did not know whether the Chevy Bolt would have enough range or a fast enough charging time for my trip, and the agent was not helpful. The Thrifty agent was also not knowledgeable of the type of SUVs that were available, but at least knew that the SUV takes premium gas.  I agree to the upgrade and am given an estimated receipt for nearly triple the $350 I was told.  I ask, does the prepaid amount apply after this, and the agent says he can’t see how much I prepaid.  It seems way too high to have already applied the prepaid amount.  Furthermore, the additional taxes were double the amount quoted in my original prepaid payment and were not explained to me why.  Lastly, it was not clear to me which of the fees and insurance I had already paid would carry over or how they would apply.     At this point I am already an hour late and the agent has not been able to answer any of my questions so I leave. Waiting for the car was a long and unpleasant experience.  Being told my car was not available and sprung with a modification to the reservation at the counter was frustrating.  They are using bad customer service to ignore a prepaid agreement and tack on extra fees. Another issue I had: I called customer service to make sure I could return the car early 12 hours early (instead of 9/9 @ 10AM, changed to 9/8 @ 10PM) and make sure I do not incur an "early rental fee." The wait was not terribly long (~15 minutes). I let the lady on the phone know that I am returning it early, and she said the rate would change to a lower amount and she would e-mail the reflection in 30-45 minutes. I did not receive an e-mail and the rental agreement remain the same on there. I decided to call back two days later to make sure the change was reflected. The guy on the phone was confused, because he said in his system it said 9/8 @ 10AM! So I had him confirmed to change it to 10PM. He then said it will change the amount, and that amount was higher than the amount the lady said, but also $3 lower than the estimated amount I originally had, which doesn't make sense because I am returning it 12 hours earlier. I asked for an e-mail and had him read it out to me. Never got an e-mail and my rental agreement remained the same online. Overall, customer service was not engaged and not helpful because they misheard me. Also, Thrifty's systems need to talk to each other. I have let Thrifty know of my poor customer experience and they said they would get back to me in 10 business days and that has never happened. I will not rent from them again.