i think that bright spark is very reasonable with his charges. we paid £150 for one days labour on a test /inspect job.it was part 10 year update on the existing part of the house and part full check on a large extension ,so that the spark treated it all as new.we had already bought a MK ccu (board), 17th edition with double RCDs for £110 and i thought that was not expensive and i was really pleased to get the work done, peace of mind, i mean.
these guys turn up with a van full of kit to overcome problems that may arise and they pay £750-£900 for a meggar tester to test the boards. i think the charges are very fair.