Cheap Car Rentals in South Side, Chicago

Well I am really pissed off to be honest. I ordered the car on the 6th of April 2023 and wanted it the morning after and just for that one day (7th of April). I get confirmation and everything looks good. I get to the place of pickup and the lady at the desk there tells me she has no cars and she's calling 15 other people in my same situation telling them she has no cars for them. Now that's a failing grade right there. The day is ruined for me and my family. I ask her to cancel my order because the only thing she could offer me is a car at 1 pm that day which is half the day gone and we had many things planned to see. So that wasn't going to work. I start looking for other cars to rent and I see there is plenty of cars from Hertz at ORD airport. So I ask the lady if I could just go there and pick up a car? She says she doesn't know because she had been busy calling these 15 people all morning. I would have thought that the best thing to do is to locate available cars and offer the people the option of getting their car at different locations if they don't want to wait until later that day. Anyway at that moment a guy walks passed her holding several car keys and she asks me to wait a second. She talks to him and gets a key from him. She tells me she got a car for me. So kudos to the lady for that. This saved the day for me and my family. However I wasn't told that Hertz would charge me $200 for what I can only assume is some security deposit. I hope I get that very soon. Then the day goes as planned and we had a great time. Except for the smell of hemp in the car, broken lighter and empty coffee cup. But hey...they probably didn't have time to clean it properly to give me the car....so I'm forgiving about that but the person who had it before me was definitely not following the no smoking vehicle rule. Now to the thing that is really pissing me off. Not the fact that I almost didn't get the car I was promised and had a confirmation email about. But the fact that every day after that I'm getting billed $100!!!! Now my guess is that they think I haven't returned the car. I most definitely did and parked it on the second floor because the first floor was full as I was told. I marked the key "2S" like asked if I had to park it on the second floor. And I put the keys in the key box like asked and shown. I checked the key box if the keys actually fell down out of the drawer, which they did. Now I have been charged $559 which is almost 10 times what I was supposed to pay for the car. My credit card is maxed out :( that is seriously annoying, embarrassing and a number of other negative things. So my experience now is this. I don't trust online booking of rental cars. I probably never will do that again.