>This assumes you do Time and Material work and not Fixed Price.


It assumes nothing of the kind... At least, not in my world...

Your fixed price K only relates to specific travel. By definiton, it cannot be open-ended. Any other "unexpected" or "extraordinary" travel would be subject to a change order and consequently, more $.

In my experience, this is where a lot of developers take a royal bath, because they fail to account for these contingencies. Sadley, it is the deal they make and one that they must stick with.