Range from the cheapest Downlights installation £250 (Mr based in TR4) to the dearest Downlights installation £340 (Matt Richards Electrical Services based in TR15).
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 TR3.