I worked as a self employed electrician for a couple of years and NEVER ignored a customer call despite the time of day (or night), also if for some reason, I wasn't going to make it on site when agreed, I would always call and let them know.
I eventually gave up because as a sole trader, I couldn't afford to knock someone back, however, I got fed up with 0700-2100 weekdays and 0900-1900 weekends - every day. Earned loads but had no life. Then this company came knocking at my door and I am still with them.
Even now we still get messed about by tradesmen.