[katla]

This is a question I’ve struggled with a lot myself. From my 15 years of experience as a contractor:

1. Never lower your rate, bringing it back up will be way harder then you might think.

2. Breaks etc. are billable. I even bill for walks that may be a long an hour, as long as I think about work. If I stop doing that I stop the clock too. Like others said, code is just the end result. I will usually produce better if I take a breather. Thinking things through will almost always let you find ways to write less code, resulting in a more stable and maintainable solution. Nothing suggests you think better while seated infront of your screen.

3. Always round up to the next hour.