over the years have worked for all kinds of people , but the ones who I find are the worst know it all / I would do it this way etc, are engineers followed by teachers , priced a job a few weeks ago for an engineer allowed for 5 bags of bonding put price in, he rang me back the next night said he would do bonding work as he had a bag of bonding in the house, would I mind , I said no knock yourself out ,remember I had allowed 5 bags, he then asked me how to mix it, so I gave him a new price skimming only, went to do job very very quiet subdued it had taken 5 bags and what a mess he had done of it, so anyhooooo got some extra work out of it putting right his work , but why do it in the first place, if I want a radiator taken off I get a plumber in I just would not tackle anything at all I know I could not do, but the thing is this is not the first engineer with this attitude seem to think they know it all