Range from the cheapest Downlights installation £240 (Smart heating & Electrics based in UB8) to the dearest Downlights installation £390 (PCC Electrical Services Ltd based in UB10).
Comparing electricians estimates for Downlights installation 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 installing downlights by posting a job to electricians in Hillingdon.