that myth about cash is not true. Dealerships prefer you finance so they can make money off the back end, and if they refer X amount of accounts to a certain bank they get a kick back.
It’s true i do pay cash, but what i do is let the dealership finance me, then I pay them off in a month or so. So they will still bring the cars price down since i let them make some back end money
the only car I thought I got a raw deal on was the Z06… paid MSRP not a cent more 
But that was in the days of 5-10k markups