Yep. The world of consulting engineering be a fickle wench. Feast or famine I always say. The questions you ask are quite typical. me_dennis gave a good response. Also, be weary of cheap clients who try to lowball you. Our company makes it a point to screen the crap out of our clients before dealing with them. And even then the cheap and/or non-paying client will squeak through.
And really your questions aren't just isolated to the engineering field. It's really a theme for consulting project management in general. Manage clients and profits, dealing with overheads, staff usage. It all comes with the territory.
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