Unsightly pipes, scorching & cracking of plaster & skirting

I’ve just had a new boiler and replacement radiators fitted in a newly decorated and plastered house. As I feel that the gas safe registered heating engineer’s work is untidy, I was dismayed when I saw it. Unfortunately, he has utilised part of the old, (unsightly), painted pipework, so that the aesthetics don’t look great. There is also extensive scorching and cracking of the newly plastered and decorated walls and skirtings where the soldering took place. This damage is present in nearly every room. As the plumber clearly feels that I am being unreasonable, to what extent is my disappointment justified? I was taken aback when I inspected the work, especially as I had emphasised to him before hiring him how important it was to me that the old pipework protruding from the ceilings be replaced with copper piping and concealed with trunking. We had the original radiators removed at the decorator’s request, so that he could decorate properly.