Range from the cheapest fitting of bespoke bookshelves £892 (London Window Painting Company based in W11) to the dearest fitting of bespoke bookshelves £1,000 (REBUILD (LONDON) LTD based in W3).
Comparing carpenter and joiners estimates for having bookshelves fitted gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.
What to do - Get rates and quotes to fit bookshelves in W12 by posting a job with HaMuch and we will send it to carpenter and joiners in W12.

"2 x fitted bookcases. Each 240x90cm"
W6
"Fitted bookcase – We would like to have fitted bookcases in the two alcoves to the left (91 cm width ) and right (100 cm width) of a fireplace."
W9