Range from the cheapest Downlights installation £299 (RNB Electrical Services based in NP4) to the dearest Downlights installation £324 (Ostler's Electrical and Plumbing based in NP16).
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 Usk.