Range from the cheapest Boiler service £38 (1953 based in DA8) to the dearest Boiler service £140 (Birdz Property Services based in DA16).
Comparing heating engineers estimates for a Boiler service 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 for a boiler service by posting your job to heating engineers in SE28