Buy a new car ordeal, how to get the best deal?

They played the oldest tricks in the book. First offer, $2000 down and $309 a month. We said no. Salesmans reply "if you want me to call the owner to give you a discount you have to say you will buy it tonight"

We said we are not "on the spot buyers" give us your best deal and we'll mole it over. He said "that's not how we work, if I am going to call the owner we need a guarantee that you will sign tonight"

We walked out. They met us in the parking lot. With 0 down and $250 a month.

After all this negotiation on payment we realized we were paying full sticker price.

Salesman said for a 2016 Honda Civic EL-X with NAV costs $25,500 and he is selling it to us for $23,500

Kelley blue book says that car retails between $21,500 and $23,500 (another scam lie)

We left cause my wife has no credit but makes $20,000 a month (she's a doctor) she said no to me co-signing that night (I have a credit score of 767)

If we go back with me co-signing with a 767 credit score and my wife's monthly income of $20,000 a month…

could we negotiate a total price of the car at an even $20,000

so my main question is can they sell a 2016 honda civic el-x with nav MSRP 23,500 for $20,000? (they are going to lie and say the MSRP is $25,000) but no matter is $20,000 too low for them or could we go any lower?

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