Zac Efron -- Post Rehab Crib -- Drops $3.9 Mil On Nice-Ish Crib

Zac Efron has found a place where he can get away from it all ... right smack in the middle of L.A.

The troubled star -- who recently completed his second stint in rehab for cocaine -- just snagged a $3.9 million hillside home in the Los Feliz area of L.A.

The seller pitched the house as super zen. It's also extremely private and, well ... it's nice.

Zac's got 5 bedrooms and endless city/ocean views.

His neighbors seem to like their privacy, too ... Kristen Stewart, "Glee" star Naya Rivera, Rose McGowan and a bunch of other celebs have bought homes in the neighborhood.