Kendrick Lamar's crash pad at Coachella's fit for a king ... dude balled out at an INSANE villa for his must-see performance out in the desert.

The "HUMBLE." rapper made himself at home at the Big Sioux Estate -- a spectacular 6 bedroom, 7.5 bathroom villa with a pretty steep price tag ... 10 million bucks. Any Joe Schmoe's looking at about $1,880 per night to stay there, but Kendrick got the pad courtesy of Airbnb.

The Rancho Mirage crib's got it all ... total privacy, a sick pool and plenty of space for a headliner to turn up.