answer:it depends, mostly on the quality of the company and whether they have good competition. It’s not unusual to have to leave a message the first time, especially the smaller 2–3 person operations – I figure they may well be hard it work. However, if they don’t respond quickly – within hours, definitely by that evening – they’re off my list. Where I live, I’m aware of 4–5 good quality plumbers and HVAC people. So if #1 doesn’t answer, then I go with #2, and so on. On the other hand, there was I guy who came in and did a great job on my roof a couple years ago—I would definitely wait for his services if I needed them. So it really depends on how badly they are needed and how good they are.