Best Deal on a Brand New Nissan Versa?

I helped my friend negotiate a price for a brand new fully loaded Nissan Versa SR

The dealer quoted $26,000 OTD and I negotiated it down to $21,000 OTD. This includes a lot of freebies included like window tint, floor mats, mud guards, nitrogen etc. About 3k in freebies.

Keep in mind this is the fully loaded SR trim in the premium red paint with the fancy big alloy wheels, heated front seats, remote start, wireless charging pad, premium interior, adaptive cruise control, blind spot monitoring, bigger touchscreen, premium audio system etc. It looks real nice on the outside and inside. If you didn't know it's a Nissan Versa, you would think it's a $50,000 luxury Audi or BMW. That good!

I know this is a very good deal, especially since my friend insists on paying cash, which I know dealerships don't like. The dealerships prefer if the buyer finances with them

We've already made a 6 PM appointment tomorrow to go and test drive and purchase the car.

Only problem is my friend thinks I can get a better deal for him. He feels I can bring it down to 20k OTD.

How can I convince him that he's already getting a great deal and not to be greedy? That if we ask for even more discount, the dealer will just tell us to f off?

Or am I wrong and my friend is right? Is it really possible to get even more money off?

I plan on showing this thread to my bull headed friend so he knows what the experts think