Range from the cheapest installing or fixing of light switches £42 (CM ELECTRICAL based in W11) to the dearest installing or fixing of lightswitches £180 (MGB Electrical Solutions Ltd based in SW6).
Comparing electricians estimates for installing or fixing light switches 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 repair or replace light switches in W14 by posting a job with HaMuch and we will send it to electricians in W14.

"Good afternoon The hallway light timer is malfunctioning in the lights remain steadily on and do not time out. Could you please quote for a replacement of the device. We are in Shepherd's Bush just off the green. best regards Matt"
W14
"Install or fix a light switch"
SW7