Derater,
When I was in business, if I found a small "fubar" I would tell the homeowner and then I might just fix it myself and tell them "No Charge". It was good for the business. However if there was something real bad, I would tell the homeowner and make them aware of the problem, ask them if the wanted me to fix it or give them a quote to fix it. I would fix it unless they told me too. ( Or get a change order.) If they didn't want me to fix it and just wanted a bill for what I did, then on my bill I would write down what I saw wrong. For example: we added 3 receptacles for $55.00 a piece and while on the job we saw that the sub panel was in violation of the NEC. If you would like a quote from our company, please let us know and we will submit a price to repair the problem.
I figure that if the person saw my bill and paid me, then they would have read my note about the violation in their house.
