I charge for what my time is worth. I'd say 70-80% of potential domestic and light commercial customers can't afford it. You might think this way of operating odd, however I'm quite happy not scraping around for chump change amongst the five week wonders and general knuckle draggers. I aim higher. My domestic clients are high end or emergency call out only, my commercial clients have exacting standards and are happy to pay the premium, my industrial clients pay the going rate for someone capable of carrying out the work knowing that they're few and far between.
When it comes to more specialist jobs, I charge an even higher premium safe in the knowledge that the level of skill involved to complete the task is not readily available on the market.
If you don't have the calls coming in, you can't afford to be choosy. If you do, you can.
The truth is, there are so many factors to take in to account when calculating an hourly, daily or job rate, that it's impossible to say that 'x' amount is 'the' going rate. There is no such thing.