Last car I bought, a Subaru Forrester, which is like 25% of cars in Seattle, I knocked $4000, off of msrp by haggling from 28k to 24k, cross shopping across dealers and walking in with a set price I was willing to pay after finding the lowest dealer. Also going in during 2 manufacturer rebates (one cash, one charity match), and at the end of the quarter. 2018s were starting to show up, bought the 2017.

They got real triggered when I said "all you gotta do to put another name up on that trophy board is come down $500 more" (they were writing all of the sales on the window as they happened).

Brought a book to read while they went in to "talk to the manager".

While there is the option to compared to 'no haggle', I can sit there and waste an hour on their BS for $4k. I find it fun and interesting, and I don't buy cars when I have to only when I want to. Helps to have multiple backup transportation methods.