That's a good point. I'm terrible at this kind of negotiation though, do you usually come in with a particular price or do they have a set amount if it's cash? I think I'd like to get better at negotiating, I usually end up paying full price for a car because of my lack of such skill.
Yeah as the other person said, you definitely don't need to be a shark, ask how much it would be if you were paying cash. Also you can always walk away from a purchase and say you'll think about it. I got a call the next day where they took $500 off of bedroom furniture when I actually was just thinking about my other options. Cars especially though you should be asking for discounts, I worked at a car dealership (in detailing, i couldn't be a salesman) and they are horrible. Also they work on purely commission so it's in their best interest to give you a deal since if they don't close they don't make anything. Walk away from a car dealership as many times as you have to... really just take your time.
Try just asking for a discount on purchases of single items above ~100€/$. It can be as simple as saying 'Can you give me a discount?'. Sometimes you get free stuff added, sometimes a few percent off. And this is just the simplest level where you don't even really negotiate, you just ask one question nicely, no conflict. Eg. hiking boots, bikes, computers are things where that worked for me.
