Auction/trade-in price vs retail price?

I'm wondering if there is a general percentage of markup that a uses car dealer makes on a car they purchase from auction or a trade-in compared to the price they actually sell the car. It seems like every dealer I talk to says they're losing money on the deal, which I know is BS. But I was wondering if they're making hundreds or thousands on these deals. For example I was looking at a 2024 Kia Sorento S that was marked as $25,000. When I plug in the trade-in value for that same car it's thousands less. So I have to assume they're making a killing on customers.