Range from the cheapest installation of a carbon monoxide alarm £74 (Gsi-Gas based in SE5) to the dearest installation of a carbon monoxide alarm £164 (Elmark Ltd based in SE20).
Comparing electricians estimates for fitting a carbon monoxide detector 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 install carbon monoxide alarm in SE21 by posting a job with HaMuch and we will send it to electricians in SE21.