This is positive surely? B&Q get so much foot traffic, maybe customers might not be so jumpy at independent fixer quotes.
Among a lot of my private work I have recently secured fixing contracts with a local high end builder at £30.00psm fixing only (materials, sealing, grouting and prep all extra).
More relevent to the topic though, im regularly subbing to a company that does the homebase installs for £150.00 day rate plus materials. Both I think are pretty good rates for non-private work.