Changes are normal. Losses are optional.

Your schedule misunderstandings and delays for subcontractors are obviously a big deal, and money is lost very, very quickly. It's not because of the work, it's because of actually the paperwork behind the work that is the biggest problem, in that you're delayed by someone else's delay and its schedule, and you've not been on top of your paperwork to submit your notice to say that this has happened. And then down the line, you're struggling, you're scrambling to try and prove that this delay was caused by this other contractor, you didn't have access to this site on whatever day, and it becomes too hard to justify, and then you don't get paid for it. That's how you lose money, is not being weak enough to get the notice in and trying to get this perfect notice in that doesn't actually exist. Just get your notice in, say, you know, the costs are going to come, and then you're good to go.