we do our fair share of bonding gas and water coz the last spark / kitchen fitter couldn't be arsed, sorting out the lack of an earth at all coz the water company has replaced the mains pipes with plastic and not thought it necessary to tell any of the houses that were relying on those pipes for earthing (which is a good proportion of Leeds houses IME) etc. I love the ones where the spark has run the earth bonding cable to the location of the sink / boiler left it for the kitchen fitter / gas boys to fit to the pipe when the install their kit, but they obviously thought bonding worked well enough as long as the cable was within site of the pipe it was bonding to, no need to actually clamp it to the pipe or anything.This is maybe a nasty thing to say - but im glad its just not us domestic/comercial sparks that see the DIY monstrositys and you solar lads get it aswell
We just also get the job of sorting out the roofers bodges as well.... then with the solar water heating side we sometimes have the joy of fixing the mess a swimming pool installer / bodger had made of a £100k pool... and that british gas had made of fitting a boiler 15 years ago with the sodding heating pump pumping the wrong way round the circuit causing the boiler to cycle hot/col/hot/cold like it was on the menopause... and the customer to wonder why their systems was rubbish and cost them a fortune......... right old can of worms that one.
keeps us on our toes though eh.