Range from the cheapest Boiler service £50 (Karol Szymanski based in BR5) to the dearest Boiler service £190 (Azbc Building Services based in DA2).
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 BR8