'Million Dollar Wheels' RD Whittington Reveals Pecking Order in Celeb Car Buying

"Million Dollar Wheels" star RD Whittington makes tough decisions when celebs are vying for the same car ... and, apologies to Spider-Man, but Kim Kardashian might get first dibs.

RD's the guy who hooks up celebs -- like Kim, Jamie Foxx, Travis Barker, Ye and Tom Holland -- when they want a rare or luxury ride, and he was hit with a doozy of a hypothetical when he joined us Monday on "TMZ Live."

So, suppose Kim K and Holland -- who, BTW, are both featured on his new Discovery+ show -- want the same car, and there's only one available. Well, hypothetically, RD didn't even break a sweat, and quickly explained why -- in that case, specifically -- he'd give Kim the nod.

Of course, if Tom were buying the car as a gift for his GF, Zendaya, well ... that would throw a wrench in RD's plans, but he still had a solution.

"Million Dollar Wheels" shows RD wheeling and dealing with, and for, famous clients -- a job that's gotten way more challenging because now there's a lot more demand than supply.

As we've shown you, tons of celebs are tricking out cars these days -- Kanye West got a $400k custom minivan from RD -- but after 20 years as a luxury car broker, RD says Jamie is the celeb with the best feel for custom whips.