Scooter Braun -- Droppin' Epic Bachelor Pad Before Fatherhood

Scooter Braun kissed bachelorhood goodbye last year ... and now he's ready to cash out on his ultimate bachelor pad to the tune of nearly $12 million.

Braun's 5,300 sq. ft. former man palace is cavernous ... no doubt Justin Bieber crashed more than once in the 4-bed, 5-bath digs Scooter bought in 2011 for $5.7 million.

The testosterdome has a pool, a cabana (for babes), a koi pond (for the koi), and massive floor to ceiling glass walls -- which possibly inspired Biebs to score a glass house too.

Scooter's wife Yael is about to have their first kid ... so the timing's right to scrub all traces of his single days. Last year they dropped $13 mill on a more family-friendly 11,137 sq. ft. mansion in Brentwood.