Bookkeeper's house with revolutionary new look (9)
I believe the answer is:
librarian
'bookkeeper's' is the definition.
(librarians look after books)
'house with revolutionary new look' is the wordplay.
'house' becomes 'libra' (house in the astrological sense).
'with' means one lot of letters go next to another.
'revolutionary' says the letters should be written backwards.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'look' becomes 'air' (I've seen this before).
'n'+'air'='nair'
'nair' reversed gives 'rian'.
'libra'+'rian'='LIBRARIAN'
(Other definitions for librarian that I've seen before include "Person in charge of books etc" , "Custodian of a collection of books" , "employee in Reading office?" , "Book keeper" , "Browsers need her" .)