New to the Forum, Very new to buying New Car

My name is Demond, I want to tell my experience buying my 2023 Kia K5 GT line. Purchase my car from Capital Kia of Columbus, I had a pre-approved from my credit union for about the price of the car plus or minus a couple of thousand, My credit union said all I have to do is call if the price varies to get the exact amount approved. This is my fourth time having a buy a car with pre-approved already which I love better, because I'm ahead of the game with the dealership, this is my first time dealing with Kia. Going to the dealership or I know what I wanted of wolf gray Kia K5 GT line I know the options might have varied but I knew what I wanted. Brandon was my salesman we work at a deal I always ask tax title out the door price, he asked me if I had a trade in I said no because I know how they work it you never tell them you have a trade in till you get your deal then you tell
them at the last minute. I had no trade in wanted to keep my old car which was a for a fusion . We agreed on a price I believe it's like close to 33,000 can't remember exact price it was the high 32s. He proceeded to ask me for my bank information I told him then that I want him to run it one time my credit because I already have a pre-approved but my credit union, My coworker at work said that they really don't like that because they can't make no money off of you. So they ran my credit nine times which I was ****** because I have pre-approved for my bank I had just got my credit together and my bank knows what I make because they see my payroll checks each week so they had no problem giving me the loan. So they send it over to my bank finally I left, next day they call and said they forgot to add some type of add-on which is another $1,400 which with some BS right there, so I agreed to it. I picked up my car after couple days after Christmas cause we had bad weather. Brandon greeted me when I got to the dealership he was starting to plot right away he asked me if I had a down payment I said heck no, The bank haven't sent no check yet or I did not sign no paperwork. He said okay let's size some paperwork so when it gets down to the cost of course it was changed already which I agreed to then he start to talk about this $1,000 again, I said what are you talking about. Somehow I ended up in the finance room and we was going back and forth over $1,000 course I started to get frustrated and start talking like I leave there's other other dealerships, so we started to go back and forth over $1,000 and somehow somebody pulled my deal up on the iPad and there was zero down my deal, the pre-proof deal save me if not they was going to want that thousand dollars or I would have left that car there. Brandon apologize said that was somebody else deal they was talking about but they was trying to get the $1,000 out of me. My point is dealerships are crooked so you got to watch them and play that game too. They hate when you come with pre-approved because they can't get no money down.